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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Glass ConstructionContents: Introduction
Historical Development of Glass Constructions
DesignMaterial Glass
Existing Guidelines
Results from Research
Suggestions for further Design-Guidelines
Load-Bearing Glass ConstructionsExamples
FEM-Analysis based on Experiments
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Introduction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
GLASS STRENGTH:GLASS STRENGTH:• Theoretical: Compressive strength:
Tensile strength: > 1000 N/mm²
• Brittleness no plasticitiy(no stress redistribution)
• Practical: Tensile strength: 30 – 100 N/mm²(notches in glass-surface)
MAIN PROBLEM:MAIN PROBLEM:
• sudden collpase by reaching the ultimate load
• linear stress-strain-relation until fracture
MATERIALMATERIAL
STEEL GLASS
700 – 900 N/mm²
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Floatglass
IMPORTANT GLASS PRODUCTS:IMPORTANT GLASS PRODUCTS:
• Standard Glass, most frequently used
• exclusive inherent strength (45 N/mm²)
• Structure after fracture:
Star-shaped large fragments
Design
MATERIALMATERIAL
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
TEMPERED GLASS (ESG)• thermally toughened safety glass• total strength: 120 N/mm²
• small, blunt crumbs
• Note: after thermal strengthening of ESG /TVGfurther processing is not possible
HEAT STRENGHTENED GLASS (TVG)• heat strengthened Floatglass• total strength: variable depending on producer
MATERIALMATERIAL
• Structure after fracture:
• Structure after fracture:(~ 70 N/mm²)
Star-shaped large fragments(similar to Floatglass)
IMPORTANT GLASS-PRODUCTS:IMPORTANT GLASS-PRODUCTS:
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
LAMINATED SAFETY GLASS (VSG):LAMINATED SAFETY GLASS (VSG):
• 2 or more panes on top of each other
load bearing capacity after fracture
• connected by PVB-Interlayers• all glass products can be combined at will• BENEFIT: fixing splinters and improved
• required for load-bearing Glass-Constructions
INSULATION GLAZING:INSULATION GLAZING:• 2 or more panes are seperated by a hermetic
interstice• connection of the panes only at the sides by
• BENEFIT: Improvement of thermal insulationseparators
Design
MATERIALMATERIAL
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
• Experiment for time-dependent strength
• Experiment for punch strength
MATERIALMATERIAL
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
t = 2min
t = 5min
t = 3 h
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
SPECIAL GLASSESSPECIAL GLASSES:
e.g. fire-protecting glasses
MATERIALMATERIAL
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
• continuous support of at least two opposite sides
• Deflection of the substructure ≤ L/200 or 15mm(L: length of glass pane)
• continuous support necessary also forlifting forces (wind suction)(e.g. stiff cover plates)
• Installation height of vertical glazing > 4m
AREA OF APPLICATION:AREA OF APPLICATION:
TRLV NOT ALLOWED FOR:TRLV NOT ALLOWED FOR:• single or additional glass fitting
• enterable glazing („walk-on“-glazing)
• single sided clamped support
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRLVTRLV
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
for Glass-Designfor Glass-Design
TRLVTRLV
Existing Guidelines Existing Guidelines
• Vertical Glazing:vertical Inclination ≤ 10°
DEFINITION:DEFINITION:
• Overhead Glazing:vertical Inclination > 10°
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
• no special requirements concerningload bearing capacity after fracture
• 4-sided support necessary (except for
VERTICAL GLAZING:VERTICAL GLAZING:
• Heat-Soak-Test (sulfide-inclusion)
tempered glass (ESG))
a) ESG-panes being supported on < 4 sidesb) ESG-panes with alternating temperature
- to avoid sudden failure of ESG-panes
• Drilling and cut-out allowed in vertical glazing
Existing Guidelines Existing Guidelines
TRLVTRLV
for Glass-Designfor Glass-Design
- prescribed for:
loading
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRLVTRLV
OVERHEAD GLAZING:OVERHEAD GLAZING:• special requirements concerning load bearing
• For single glazing and lower panes ofinsulation glazing is allowed to use:a) Laminated safety glass (VSG) with Floatglass
b) Wired Glass
• Larger spans possible, if there areadditional safety devices
Span > 1,20m needs to have 4-sided support
Applicable only for spans ≤ 70 cm
Avoid glass pieces falling down tocirculation areas
(e.g. by a close meshed net)
capacity after fracture
• Drilling and cut-out NOT allowed in overheadglazing
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
DESIGN:DESIGN: Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRLVTRLV
• Basis: Concept of allowable stresses
• composite shear-effect of laminated glass isnot allowed to be respected
• factors increasing stresses are to be respected
More modern concepts are involved bydifferent sizes of allowable stresses for verticaland overhead glazing (because of differentdurations of load actions).
e.g. drilling, sections
• stick to maximum deflections
1812Floatglass
22,515VSG (Float)
5050ESG (Float)
VerticalOverheadGlass product
Allowable stresses [N/mm²]
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRLVTRLV
SPECIALTIES CONCERNING INSULATING GLAZING:SPECIALTIES CONCERNING INSULATING GLAZING:• Additional to „standard“ load-assumptions
there are differences in pressures between
a) Differences of temperaturesb) Differences in heights (place of
production and installation)c) Changes of air pressure
interstice and environment:
• Effect of interconnection between the panesis to be respected
• In case of failure of overhead glazing:The lower pane must be designed to bear theloads of the upper pane
(in this case: no requests concerning deflections)
• TRLV needs not to be used for windows bysticking to some criterias:(e.g. height of installation ≤ 20m,
size of window ≤ 1,6m²)
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRAVTRAV
TRAV NEEDS NOT TO BE USED FOR:TRAV NEEDS NOT TO BE USED FOR:
• Glass to prevent from falling, differencein height ≥1,0m
• vertical glazing (TRLV) with additional demands
• linear beared parapet with passing structuralhandrail
• glass elements used as filling
• glass elements that do not prevent from fallingindependently
(additional structural elements are used to do so, e.g. flat grids)
AREA OF APPLICATION:AREA OF APPLICATION:
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRAVTRAV
Category A
CLASSIFICATION IN 5 CATEGORIES:CLASSIFICATION IN 5 CATEGORIES:
CATEGORY A
• high vertical glazings without anyhandrail or bar
• horizontal forces must be beared bythe glazing
• VSG for single glazing and for the inner pane of insulation glazing
• any glass product for the outer paneof insulation glazing
APPLICABLE GLASS PRODUCTS:
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Category B
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRAVTRAV
CATEGORY B
• Forces from the handrail must be bearedby the glazing
• only VSG
• parapet-high vertical glazing elementswith linear beared fixing at the bottomand a passing structural handrail
• In case of collapse of a glass-elementthe forces must be transmitted by thehandrail to the adjacent elements
APPLICABLE GLASS PRODUCTS:
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Category C1
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRAVTRAV
CATEGORY C
• Filling with at least two facing sides being beared linear or by glass fittings
C1
Category C2
Category C3
• having a load-bearing bar above vertical glasselements that are fixed linear at at least two facingsides
C2
• Glazing like Categrory A but with an additionalstructural handrail
C3
• single glazing: only VSG
ESG with a four-sided linear bearing• Exception for C1 and C2:
• ESG is possible for the inner pane of insulation glazing
APPLICABLE GLASS PRODUCTS:
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRAVTRAV
DESIGN:DESIGN:
ACTIONS• Wind (w), Force of handrail (h)• Climatic loads in case of insulation glazing
COMBINATIONS OF ACTIONS:• In general: w+h/2 and h+w/2• for insulation glazing additionally:
w+climatic loads and h+climatic loads• „Crash“-loads (not to be combined)
VERIFICATION:• allowable stresses according to TRLV
• Effect of interconnection between thepanes of insulation glazing can be used
• composite shear-effect of laminated glassIs not allowed to be respected
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Existing Guidelines Existing Guidelines for Glass-Designfor Glass-Design
TRAVTRAV
IMPACT LOADS:IMPACT LOADS:
EXPERIMENTAL VERIFICATION• Pendulum impact test
MATHEMATICAL VERIFICATION
STICKING TO DESIGN CRITERIAS, e.g.
- testing heights: 45 cm (Cat. C) – 70 cm (B) - 90cm (A)- different testing locations- bearing conditions must be modelled correctly(possibly experiments at the real unit)
• Several criterias must be fulfilled, e.g.:- linear bearing of the glazing- limitations of the pane-sizes
• allowable stresses can be increased forimpact loads
(Float: 80 N/mm², ESG: 170 N/mm²)
• no drillings or cut-outs• minimum overlapping size glass / fixation:
• requirements concerning the fixation12 to 14mm
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
BEMESSUNG:BEMESSUNG:
• High stresses at the edges of drillings mustbe avoided
• Exact modelling of the support area isnecessary
• Expendable FEM-Analysis
• Often experiments are necessary to validatemathematical results
PUNKTHALTERPUNKTHALTER
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
GRIPPING JAWS:GRIPPING JAWS:• no drillings in the pane
Beared by the jaws
• jaws on both sides
• Forces perpendicular to the pane:
Beared by setting blocks and / or• Forces in-plane:
(partially) by friction
GLASS FITTINGGLASS FITTING
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
DRILLED GLASS FITTINGS:DRILLED GLASS FITTINGS::• Glass needs to be pierced
• Glass fitting systems support both, single
• Effects of rigid fixing in the area of the glass fittings
• BENEFIT: filigree, transparent facades
dangerous stress concentrations
and insulation glazing
Qualtiy of the edges of the drilling effects the load bearing capacity
GLASS FITTINGGLASS FITTING
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
Total collapse of an VSG-Glazing-System
Snap out of the PVB-Interlayer
GLASS FITTINGGLASS FITTING
from the glass fitting
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
GLASS FITTINGGLASS FITTING
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
GLASS FITTINGGLASS FITTING
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
DESIGN CONCEPTSDESIGN CONCEPTS
CURRENT STATUS:CURRENT STATUS:
• Design according to allowable stresses• global safety factor• linear bending theory
PROBLEMS:PROBLEMS:
• strength of glass depends on several factors:(e.g. surface defects, environmental impacts)
• there is no „absolute“ strength definable
• Deflections can go up to multiple glass thickness
• nonlinear design becomes necessary
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
MODERN CONCEPTS:MODERN CONCEPTS:
• Design on probability of failure:
• Regarding strength-influencing factors:
- crack starts in areas that offers relatively high stresses
Cracks do not start in areas with the highest stresseswith a relatively deep notch
- Quality of the surface (deepness of notches)
- Size of the glass elements
- Kind of loading
- Length of loading (time)
- Environmental impactsDESIGN CONCEPTSDESIGN CONCEPTS
- Implementation of safety classes:Class 1: No danger for human life Gefahr G = 8,4 · 10 -3
Class 2: Danger for human life G = 1,5 · 10 -3
calculating σeff by integrating the mean tensile stresses
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
CONCEPT FOR THE EUROPEAN NORM:CONCEPT FOR THE EUROPEAN NORM:• includes all the named influences by partial safety factors
DESIGN CONCEPTSDESIGN CONCEPTS
ACTION:• e.g. dead load, wind, snow, climatic loads, imposed deformation
Depending on safety class1,2 – 1,5fluctuating
-0,15 – 0,96Side effects
-1,35persistent
notePSFAction
REACTION:• characteristic strength of glass-products (e.g. Float: 45 N/mm²)
1,0m² - 20,0m²1,0 – 0,88Size of panes
Safety class 1 / 20,55 / 0,5Safety class
long - short0,27 – 0,72Length of action
notefactorInfluence
• using factors to reduce characteristic strength
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
RESEARCHRESEARCH
LAMINATED SAFETY GLASS:LAMINATED SAFETY GLASS: • Composite shear effect of the PVB-Interlayer
Time-DependenceTemperature-Dependence
• Reducing the brittleness of glassBENEFIT: combination of transparency and ductility
Stiffness-Dependence (support / midspan)
LAMINATED GLASS / POLYCARBONATE SANDWICH:LAMINATED GLASS / POLYCARBONATE SANDWICH:
• Realizing transparent, 3-dimensional
BENEFIT: Getting a simple connection method for:
NYLON-3D-VERBINDUNGSKNOTEN:NYLON-3D-VERBINDUNGSKNOTEN:
connections for glass constructions
Beams
Columns
Plates
Panels
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
LOAD-BEARING GLASS
LOAD-BEARING GLASS
Construction
MODERN FIELDS FOR GLASS:MODERN FIELDS FOR GLASS:
• Glassbeams
• Glasscolumns
• load bearing Glasspanels
• stiffening / bracing with glass elements
GLASS-STEEL-CONSTRUCTIONS:GLASS-STEEL-CONSTRUCTIONS:• Glass is connected to steel elements
ALL-GLASS CONSTRUCTIONS:ALL-GLASS-CONSTRUCTIONS:• Connections Glass / Glass by
silicone compound systems
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction LOAD-BEARING GLASS
LOAD-BEARING GLASS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
pw = 0,2 kN/m²Horizontal: wind
ps = 0,375 kN/m²Vertical: snow
pv = 10,5 kN/m²Vertical: Use of balcony
Live Load:
gD = 0,45 kN/m²Overhead glazing
gG = 0,30 kN/m²Grid Dead Load:
Load Assumptions:
Construction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction
F1 = 4,20 kN
F2 = 9,01 kN
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction Linear Buckling Analysis Nonlinear Buckling Analysis (zweiwellige Vorverformung mit L/200 = 14,2 mm, feste Lagerung)
CRITICAL LOAD:
156 kN (2x78 kN)
σy
uz
x
y
σx
σy
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction
Lastfall 1: Lastfall 2:
• Dreiseitige Lagerung(oberer Rand frei)
ERMITTLUNG DER VORVERFORMUNG:
• Ermittlung der Beuleigenform
EXPERIMENTSEXPERIMENTS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction
σyσx
Spannungsverteilung infolge Störlast und Eigengewicht• Vorverformung auf L/500 = 2mm
Störlast
EXPERIMENTSEXPERIMENTS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Nichtlineare Grenzlastermittlung• Vorverformung L/500 = 2mm
• Problem: festigkeitsreduzierter Kantenbereich
Construction
σyσx
GRENZLAST: 2,48 kN
Es wird eine Zugfestigkeit von 22 N/mm² für den Kanten- und Eckbereich angenommen
EXPERIMENTSEXPERIMENTS
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
σx
Construction
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Construction
σy
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
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Civil & Structural EngineeringBauhaus-University Weimar Department of Steel Structures
Design
THERMISCHE VORSPANNUNG:THERMISCHE VORSPANNUNG:
• gilt für ESG und TVG
DESIGN CONCEPTSDESIGN CONCEPTS
angesetzt werden• Vorspannung darf nicht als Materialfestigkeit
• Berücksichtigung der Vorspannung als Lastfall
• Begründung:
Für Bruchwahrscheinlichkeit ist Kenntnis der Eigen-festigkeit (Biegefestigkeit) notwendig
- Bei resultierender Druckspannung auf Oberflächewäre Lebensdauer theoretisch unendlich groß
Aussage über Lebensdauer treffen- Lebensdauer abhängig von Größe der resultierenden
Zugspannung
σBiegefestigkeit = σPrüffestigkeit + σVorspannung
[σVorspannung = negativ]