Workshop ‘Structural Fire Design of Buildings according to the Eurocodes’ – Brussels, 27-28 November 2012 1 Fire resistance assessment of timber structures Basic design methods Worked examples FRANGI Andrea Member of CEN/TC250/SC5 and HGF ETH Zurich Institute of Structural Engineering
108
Embed
Fire resistance assessment of timber structures - …eurocodes.jrc.ec.europa.eu/.../08-FRANGI-EC-FireDesign-WS.pdf · Workshop ‘Structural Fire Design of Buildings according to
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 1
Fire resistance assessment of timber structures Basic design methods Worked examples
FRANGI Andrea
Member of CENTC250SC5 and HGF
ETH Zurich Institute of Structural Engineering
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 2
London 9 storeys (UK)
Berlin 7 storeys (Germany)
Vaumlxjouml 8 storeys (Sweden)
Bolzano 7 storeys (Italy)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 3
What is Eurocode 5
Eurocode 5 (EN 1995) provides rules for the design of timber structures EN 1995-1-2 is the Fire Part of Eurocode 5 The two other parts of Eurocode 5 are EN 1995-1-1 Common rules and rules for buildings EN 1995-2 Bridges
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 4
EN 1995-1-2 deals with passive methods of fire protection EN 1995-1-2 gives design rules for the verification of the bull load-bearing function bull separation function
Scope of EN 1995-1-2
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 5
Insulation I Integrity E Load-bearing R
Passive methods of fire protection Main objective limitation of the spread of fire by guaranteeing
the load-carrying capacity of the structure (Requirement on Mechanical Resistance R)
the separating function of walls and floors (Requirement on Insulation I and Integrity E)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 6
Load-bearing elements without
separating function
Non-load-bearing elements with
separating function
Load-bearing elements with
separating function
Fire exposure
On all sides
On only one side
On only one side
Columns beams Walls Floors
Basic fire requirements
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 7
Timber behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 8
Pyrolysis thermal degradation of wood producing combustible gases and accompanied by a loss in mass (starting from about 250degC)
Charring rate β Ratio between charring depth dchar and fire time t (in mmmin)
tdchar=β
minmmminmm
tdchar 80
6350
===β
Fire time t = 63min
Residual cross-section
Char layer
Timber behaviour in fire
Material behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 9
depends on fire exposure
constant value for
ISO-fire exposure
depends on wood
species
spruce β asymp 07 mmMin
small influence of
moisture content and
density of wood
Grundlagen ldquoHolz-Brandrdquo
Charring rate
Charring depth (mm)
Mean value fire tests
Fire time (min)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 10
Char layer protects the residual cross-section from high temperatures
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 2
London 9 storeys (UK)
Berlin 7 storeys (Germany)
Vaumlxjouml 8 storeys (Sweden)
Bolzano 7 storeys (Italy)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 3
What is Eurocode 5
Eurocode 5 (EN 1995) provides rules for the design of timber structures EN 1995-1-2 is the Fire Part of Eurocode 5 The two other parts of Eurocode 5 are EN 1995-1-1 Common rules and rules for buildings EN 1995-2 Bridges
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 4
EN 1995-1-2 deals with passive methods of fire protection EN 1995-1-2 gives design rules for the verification of the bull load-bearing function bull separation function
Scope of EN 1995-1-2
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 5
Insulation I Integrity E Load-bearing R
Passive methods of fire protection Main objective limitation of the spread of fire by guaranteeing
the load-carrying capacity of the structure (Requirement on Mechanical Resistance R)
the separating function of walls and floors (Requirement on Insulation I and Integrity E)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 6
Load-bearing elements without
separating function
Non-load-bearing elements with
separating function
Load-bearing elements with
separating function
Fire exposure
On all sides
On only one side
On only one side
Columns beams Walls Floors
Basic fire requirements
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 7
Timber behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 8
Pyrolysis thermal degradation of wood producing combustible gases and accompanied by a loss in mass (starting from about 250degC)
Charring rate β Ratio between charring depth dchar and fire time t (in mmmin)
tdchar=β
minmmminmm
tdchar 80
6350
===β
Fire time t = 63min
Residual cross-section
Char layer
Timber behaviour in fire
Material behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 9
depends on fire exposure
constant value for
ISO-fire exposure
depends on wood
species
spruce β asymp 07 mmMin
small influence of
moisture content and
density of wood
Grundlagen ldquoHolz-Brandrdquo
Charring rate
Charring depth (mm)
Mean value fire tests
Fire time (min)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 10
Char layer protects the residual cross-section from high temperatures
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 3
What is Eurocode 5
Eurocode 5 (EN 1995) provides rules for the design of timber structures EN 1995-1-2 is the Fire Part of Eurocode 5 The two other parts of Eurocode 5 are EN 1995-1-1 Common rules and rules for buildings EN 1995-2 Bridges
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 4
EN 1995-1-2 deals with passive methods of fire protection EN 1995-1-2 gives design rules for the verification of the bull load-bearing function bull separation function
Scope of EN 1995-1-2
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 5
Insulation I Integrity E Load-bearing R
Passive methods of fire protection Main objective limitation of the spread of fire by guaranteeing
the load-carrying capacity of the structure (Requirement on Mechanical Resistance R)
the separating function of walls and floors (Requirement on Insulation I and Integrity E)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 6
Load-bearing elements without
separating function
Non-load-bearing elements with
separating function
Load-bearing elements with
separating function
Fire exposure
On all sides
On only one side
On only one side
Columns beams Walls Floors
Basic fire requirements
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 7
Timber behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 8
Pyrolysis thermal degradation of wood producing combustible gases and accompanied by a loss in mass (starting from about 250degC)
Charring rate β Ratio between charring depth dchar and fire time t (in mmmin)
tdchar=β
minmmminmm
tdchar 80
6350
===β
Fire time t = 63min
Residual cross-section
Char layer
Timber behaviour in fire
Material behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 9
depends on fire exposure
constant value for
ISO-fire exposure
depends on wood
species
spruce β asymp 07 mmMin
small influence of
moisture content and
density of wood
Grundlagen ldquoHolz-Brandrdquo
Charring rate
Charring depth (mm)
Mean value fire tests
Fire time (min)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 10
Char layer protects the residual cross-section from high temperatures
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 4
EN 1995-1-2 deals with passive methods of fire protection EN 1995-1-2 gives design rules for the verification of the bull load-bearing function bull separation function
Scope of EN 1995-1-2
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 5
Insulation I Integrity E Load-bearing R
Passive methods of fire protection Main objective limitation of the spread of fire by guaranteeing
the load-carrying capacity of the structure (Requirement on Mechanical Resistance R)
the separating function of walls and floors (Requirement on Insulation I and Integrity E)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 6
Load-bearing elements without
separating function
Non-load-bearing elements with
separating function
Load-bearing elements with
separating function
Fire exposure
On all sides
On only one side
On only one side
Columns beams Walls Floors
Basic fire requirements
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 7
Timber behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 8
Pyrolysis thermal degradation of wood producing combustible gases and accompanied by a loss in mass (starting from about 250degC)
Charring rate β Ratio between charring depth dchar and fire time t (in mmmin)
tdchar=β
minmmminmm
tdchar 80
6350
===β
Fire time t = 63min
Residual cross-section
Char layer
Timber behaviour in fire
Material behaviour in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 9
depends on fire exposure
constant value for
ISO-fire exposure
depends on wood
species
spruce β asymp 07 mmMin
small influence of
moisture content and
density of wood
Grundlagen ldquoHolz-Brandrdquo
Charring rate
Charring depth (mm)
Mean value fire tests
Fire time (min)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 10
Char layer protects the residual cross-section from high temperatures
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Connection with side steel plates and annular ringed
shank nails
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 69
Simplified rules ndash fire resistance determined by thickness of side members and protective panels and fastener endedge distances
Reduced load method ndash lsquoload-carrying capacity vs timersquo assumed as one-parameter exponential empirical model
afi
a3
a4
afi
afi a4
afi
t1
Connections with side members of wood
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 70
Connections designed according to EN 1995-1-1
Fastener connector type
Fire resistance tdfi [min]
Provisions
Nails 15 d ge 28 mm
Screws 15 d ge 35 mm
Bolts 15 t1 ge 45 mm
Dowels 20 t1 ge 45 mm
Connectors (EN 912) 15 t1 ge 45 mm
d is the diameter of the fastener t1 is the thickness of the side member
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 71
Greater fire resistance (not exceeding 30 min) by increasing
thickness of side members
width of the side members
end edge distance to fasteners
afi
a3
a4
afi
afi a4
afi
t1
βn is the notional charring rate kflux is a coefficient taking into account increased heat flux through the fastener treq is the required fire resistance tdfi is the fire resistance of the unprotected connection (previous table)
Simplified rules ndash unprotected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 72
Wood panelling wood-based panels or gypsum plasterboard type A or H
Gypsum plasterboard type F
tch is the time until start of charring of the protected member tch = tch (hp) treq is the required fire resistance tdfi is the fire resistance of the unprotected connection
hp afi
glued-in plugs
additional protection using panels
fasteners fixing of the additional protection
member providing protection
bolt head
afi
member
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 73
Fixing of additional protection by nails or screws
Distance between fasteners le 100 mm (along the boards edges)
le 300 mm (for internal fastenings)
Edge distance of fasteners ge afi
Penetration depth of fasteners ge 6middotd (wood-based panels or gypsum plasterboard type A or H)
ge 10middotd (gypsum plasterboard type F)
afi
afi
afi
afi hp
additional protection using panels
fasteners fixing of the additional protection
la
char layer panel
unburnt timber
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 74
Connections with internal steel plates
width bst of the steel plate
(with unprotected edges)
steel plates narrower than the timber member are protected if
bst
dg
dg
dg
dg
dg
dg
hp
hp
Unprotected edges in general
R30 bst ge 200 mm
R60 bst ge 280 mm
Unprotected edges in one or two sides
R30 bst ge 120 mm
R60 bst ge 280 mm
plate thickness le 3 mm R30 dg ge 30 mm
R60 dg ge 60 mm
joints with glued-in strips or protective wood based boards
R30 dg or hp ge 10 mm
R60 dg or hp ge 30 mm
Simplified rules ndash protected connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 75
lsquoLoad-carrying capacityrsquo vs Fire resistance assumed as one-parameter exponential empirical model
model parameter k for each connection type and limited to a maximum fire exposure period
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 76
Load-carrying capacity after a given fire exposure
EN 1995-1-1
Connection type
k
Maximum period of validity for k
Nails and screws 008 20 min
Bolts wood-to-wood (d ge 12) 0065 30 min
Bolts wood-to-wood (d ge 12) 0085 30 min
Dowels wood-to-wooda (d ge 12) 004 40 min
Dowels steel-to-wooda (d ge 12) 0085 30 min
Connectors (EN 912) 0065 30 min a requires one bolt for every four dowels
FvRk is the characteristic load-carrying capacity at normal temperature tdfi is the design fire resistance (in minutes) kfi is a factor to convert 5-percentile values to 20-percentile γMfi is the partial safety factor for timber in fire
Connections Reduced load method
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 77
Connections Reduced load method Fire resistance for a given load level
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 78
Steel-to-timber dowelled connection with internal steel plate
Ed = 40 kN Ed
a1 = 84 mm a3 = 84 mm
a4 = 55 mm
a2 = 50 mm
a4 = 55 mm
GL 24h rarr ρk = 380 kgm3
Oslash12 dowels class 68 rarr fu = 600 Nmm2
tdfi ge 30 min
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 79
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 80
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 81
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 82
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 83
Connections Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 84
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 85
Charring behaviour
Timber with steel plates Timber with steel plates and steel dowels
Timber
850
700
580
400
200
20
Temp [degC] 850
700
580
400
215
74
Temp [degC] 850
700
580
400
230 114
Temp [degC]
Influence of steel plates and steel dowels on charring
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 86
Fire design model for multiple shear steel-to-timber dowelled connections
Rdtfi = Aef ft0k kfi
t1 thickness of timber side member
Connections with steel elements in fire
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 87
Fire design model for multiple shear steel-to-timber dowelled connections
Fire design model for multiple shear steel-to-timber dowelled connections
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 88
bull Parametric fire exposure bull Advanced calculation methods bull Load-bearing timber frame assemblies with
cavity insulation bull Charring of members in wall and floor
assemblies with void cavities bull Analysis of the separating function of wall and
floor assemblies
Informative annexes
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 106
Fire safety plan with all fire safety measures
Careful planning and detailing
Professionally implementation of fire safety measures during the execution
Periodic controls and maintenance
The intensity of maintenance and controls must be set depending of the type of structures and the type and importance of the building
Quality of construction
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 107
bull EN 1995-1-2 has filled many gaps in the knowledge of structural timber design in fire
bull However some problems are still to be solved hopefully before the next generation of Eurocodes will be published
bull Further knowledge in ldquoFire safety in Timber Buildingsrdquo Technical guideline for Europe SP Report 2010
Concluding remarks
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 108
bull Simplification (ldquoonly one design principle shall be availablerdquo)
bull Harmonisation (Annexes should be moved to the main part other parts and other ENs)
bull Improvement extension bull Cross-laminated timber panel (new rules) bull Timber-concrete-composite elements
(new rules) bull Connections (Improved rules) bull Failure of claddings (Improved rules) bull Separating function (Improved rules)
Future evolution EN 1995-1-2 bull Evolution group D Dhima A Frangi (Chair) A Just P Kuklik
J Schmid N Werther
Slide Number 1
Slide Number 2
What is Eurocode 5
Scope of EN 1995-1-2
Slide Number 5
Slide Number 6
Slide Number 7
Slide Number 8
Slide Number 9
Slide Number 10
Slide Number 11
Slide Number 12
Slide Number 13
Slide Number 14
Slide Number 15
Slide Number 16
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Slide Number 21
Slide Number 22
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
Slide Number 32
Slide Number 33
Slide Number 34
Slide Number 35
Slide Number 36
Slide Number 37
Slide Number 38
Slide Number 39
Slide Number 40
Slide Number 41
Slide Number 42
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
Slide Number 49
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 53
Slide Number 54
Slide Number 55
Slide Number 56
Slide Number 57
Slide Number 58
Slide Number 59
Slide Number 60
Slide Number 61
Slide Number 62
Slide Number 63
Slide Number 64
Slide Number 65
Slide Number 66
Slide Number 67
Slide Number 68
Slide Number 69
Slide Number 70
Slide Number 71
Slide Number 72
Slide Number 73
Slide Number 74
Slide Number 75
Slide Number 76
Slide Number 77
Slide Number 78
Slide Number 79
Slide Number 80
Slide Number 81
Slide Number 82
Slide Number 83
Slide Number 84
Slide Number 85
Slide Number 86
Slide Number 87
Slide Number 88
Slide Number 89
Slide Number 90
Slide Number 91
Slide Number 92
Slide Number 93
Slide Number 94
Slide Number 95
Slide Number 96
Slide Number 97
Slide Number 98
Slide Number 99
Slide Number 100
Slide Number 101
Slide Number 102
Slide Number 103
Slide Number 104
Slide Number 105
Slide Number 106
Slide Number 107
Slide Number 108
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 89
bull Thermal analysis Effective thermal properties include effects of mass transport and cracking and surface recession of char-layer (only valid for standard fire exposure)
bull Structural analysis
Thermo-mechanical properties include transient effects of combined moisture and elevated temperature and mechano-sorptive creep
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 90
Advanced calculation methods (eg FE analysis)
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 91
Timber frame assemblies with cavities completely filled with insulation
b b
d char
n
hModification factors kmodfi are given
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 92
Fire separating function of walls and floors
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 93
bull Criterion I (insulation) bull ∆T le 140k
(average temperature rise) bull ∆T le 180k
(maximum temperature rise)
bull Criterion E (integrity) bull no sustained flaming or hot gases
to ignite a cotton pad bull no cracks or openings in
excess of certain dimensions
Insulation I
Integrity E
Requirements for separating function
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 94
ins ins0i pos ji
=sumt t k k
Components additive method
Separating function of wall and floor assemblies
Calculation of the time tins by adding the contribution to the fire resistance of the
different layers
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 95
Components additive method
ins ins0i pos ji
=sumt t k k
Basic value of layer i
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 96
ins ins0i pos ji
=sumt t k k
Position coefficient
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 97
The coefficient kpos considers the influence of the position of the layers in the assembly
tins1 gt tins2
Coefficients of design model
Position coefficient kpos
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 98
ins ins0i pos ji
=sumt t k k
Joint coefficient for joints not backed
by eg battens
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 99
ba dc b
Heat paths
Components additive method
Separating function of wall and floor assemblies
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 100
1 Wall ndash Fire resistance EI 60 Geometry
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 101
2 Wall ndash Fire resistance EI 60 Basic value of layers
Layer 1 Gypsum plasterboard type A 125 mm
Layer 2 Plywood 12 mm
Layer 3 Rock fibre batts 80 mm ρ = 26 kgm3
Layer 4 Plywood 12 mm
Layer 5 Gypsum plasterboard type A 125 mm
Separating function Worked example
min5175141h41t p0ins =sdot=sdot=
min11h950h950t pp0ins =sdot=sdot=
min16018020kh20t densinsi0ins =sdotsdot=sdotsdot=
min11h950h950t pp0ins =sdot=sdot=
min5175141h41t p0ins =sdot=sdot=
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 102
3 Wall ndash Fire resistance EI 60 Position coefficients
Separating function Worked example
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 103
4 Wall ndash Fire resistance EI 60 Joint coefficients
Layer 1 to 4 kj = 10 (layer backed by other layer)
Layer 5 kj = 10 (filled joints)
Separating function Worked example
ins ins0i pos ji
=sumt t k k
Workshop lsquoStructural Fire Design of Buildings according to the Eurocodesrsquo ndash Brussels 27-28 November 2012 104