DL PROFESSIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA 中华人民共和国行业标准 P DL 5022-1993 Technical Stipulation for the Design of Civil Structure of Thermal Power Plant 火力发电厂土建结构设计技术规定 Issued on June 15, 1993 Implemented on October 1, 1993 Issued by the Ministry of Electric Power Industry of the People’s Republic of China
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DL PROFESSIONAL STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
中华人民共和国行业标准
P DL 5022-1993
Technical Stipulation for the Design of Civil
Structure of Thermal Power Plant
火力发电厂土建结构设计技术规定
Issued on June 15, 1993 Implemented on October 1, 1993
Issued by the Ministry of Electric Power Industry of the People’s Republic of China
Professional Standard of the People’s Republic of China
中华人民共和国行业标准
Technical Stipulation for the Design of Civil Structure of
Thermal Power Plant
火力发电厂土建结构设计技术规定 DL 5022-93
Chief development organization: Northwest Electric Power Design Institute of
Ministry of Power Industry
Approval department: Ministry of Power Industry of the People's
Republic of China
China Water Power Press
水利水电出版社 Beijing 1993
Ministry of Power Industry of People's Republic of China
Notice on publishing the power professional standard of "Technical
Stipulation for the Design of Civil Structure of Thermal Power Plant”
Dian Ban (1993) No.132
Design Institute of Power Planning in our department organizes Northwest Electric
Power Design Institute to make revision for the original professional standard "Technical
Stipulation for Soil of Thermal Power Plant" (SDJ 64-84). After the examination by the
ministry, it is now approved to be a power professional standard and to be issued. Standard
serial number is DL 5022-93, which was implemented on October 1st, 1993. The original
bureau standard SDGJ 64-84 shall be abolished simultaneously.
This standard is under the jurisdiction of Design Institute of Power Planning and
Northwest Electric Power Design Institute is responsible for the explanation of this standard.
Please inform the jurisdiction organization the problems and opinions appeared in
implementation process.
This standard is published and distributed by China Water Power Press.
June 15, 1993
1
Contents
1 General provisions.................................................................................................................. 1
1.0.1 This standard is formulated with a view to go through with national technical economy
policy in the design of civil structure of thermal power plant, and to make safety and usability,
state-of-art technology, economy and rationality as well as guarantee quality.
1.0.2 This stipulation is applicable to the design of civil structure of the thermal power plant
with steam turbine generator capacity is 12-600 MW (hereinafter referred to as power plant).
For the power plant with renovation and other generator capacity, the design may refer to
stipulation and relevant specifications to. Power transformation truss may comply with
"Technical Stipulation for the Design of Building Structure in 35-500 kV Substation".
1.0.3 This stipulation is established according to current relevant standards of the nation and
be combined with characteristics of power plant. Parts not mentioned in this standard shall
still meet the requirement of current relevant standard of the nation.
1.0.4 Structural design shall meet the requirements of strength, stabilization, distortion, crack
resistance and earthquake resistance, etc.
Structural arrangement shall closely cooperate with technology; it shall design according
to unified modular system and give priority to adopting standard design and typical design to
improve level of standardization, serialization, and generalization.
1.0.5 Structural design shall base upon summarization of practical experience and scientific
experiment, and digest and absorb advanced experience in abroad, then closely cooperate
with construction, adopt new technique, new arrangement, new construction, and new
material positively and cautiously.
1.0.6 Spread and apply computer aided design technology positively and increase design level
and work efficiency continually.
1.0.7 When making structural design, it shall adopt different safety classes according to
possible seriousness of consequence caused by structural damage.
2
2 Load
2.1 Basic requirements
2.1.1 Design load and load effect combination generally constructed by power plant shall be
adopted according to the stipulation of this Chapter.
Load and load effect combination of special construction in the power plant shall be
adopted according to relevant chapters of this standard.
This specified load is the normal value in the design of building structure.
2.1.2 Load in structures may be divided into the following three kinds:
2.1.2.1 Permanent load (dead load): during application period of structure, the load value will
not vary as time, or its variation may be negligible comparing with average value, such as self
weight structure and earth pressure, etc.
2.1.2.2 Variable load (live load): during application period of the structure, load value varies
as time and its variation is non-negligible comparing with its average value, such as floor
(ground) live load, roofing live load, crane load, wind load and snow load, etc. Note: load on mill construction equipment and pipeline (including sole weight of equipment and pipeline as well as filler
weight in the equipment, pipeline and container shall be considered as live load).
2.1.2.3 Accidental load: load not always appears during application period of the structure,
once it appears, its value is very large, and its duration is short, such as blasting power and
impact force, etc.
2.1.3 Partial load factor of the general load is adopted according to the stipulation of "Load
Specifications for Building Structure.”
Load on equipment and pipeline includes coal (coal dust) in coal (fine coal) scuttle,
deaerator , industrial water tank, tailing classifier and high (low) pressure heater, etc. Its
partial load factor is 1.3.
2.1.4 Load effect combination shall not only comply with "Load Specifications for Building
Structure,” but also comply with the following supplementary provisions:
2.1.4.1 Load effect combination of the main building frame-bent may adopt the following
γQi——Partial load factor of floor live load: when normal value of live load is less
than 4 kN/m2, it takes 1.4; when normal value of the live load is no less than 4
kN/m2, it takes 1.3;
Use normal value of floor live load to calculate mainframe, which shall be adopted
3
according to table 2.2.2 of this standard;
Qik——Live load on equipment and pipeline includes coal (coal dust) in coal scuttle,
deaerator and deoxidize water tank (containing water weight), tailing classifier and
high (low) pressure heater, etc. as well as load on supporter and hanger of the
pipeline. For crane load and crane sole weight (earthquake effect combination)
respectively;
ψci, ψQi——Factor of load combination value of floor live load and load on
equipment (pipeline) in making earthquake effect combination respectively, they are
adopted according to table 9.3.4 of this standard;
ψw——Combination value factor of wind load participating in earthquake effect, the
general frame-bent structure ψw=0, boiler cradle takes ψw=0.2;
wk——Normal value of wind load. Note: load effect factors are omitted in formula (2.1.4-1)—formula (2.1.4-6)
2.1.4.2 Load effect combination value of frame beam in main building and column sections,
they may be designed according to the most disadvantageous conditions may be appeared in
the following:
Beam Mmax and its correspondent N, V;
Mmin and its correspondent N, V;
Vmax and its correspondent M, N
Column Mmax and its correspondent N, V;
Mmin and its correspondent N, V;
Nmax and its correspondent M′, V;
Nmin and its correspondent M′, V
Substratum column of the frame shall add the following two combinations besides the
aforementioned combinations:
Vmax and its correspondent M, N;
Vmin and its correspondent M, N Note: M′ is the combination according to positive (+M) and negative (-M) of the correspondent M value, but it only output
one group which is with larger value for the absolute value of M.
2.1.4.3 Buildings give priority to wind load design, such as chimney overhead bridge for coal
conveyer, gable of the main building, open style constructions with tectum, etc. when wind
load combined with dead load and other live load, factor of load combination value of the
wind load takes 1.0.
2.1.4.4 When the frame-bent load effects are combining together, it generally doesn't consider
temporary load of transportation for large pieces and hoisting, etc. during construction and
installation. It shall adopt provisional measures to solve them. If necessary, it may make
strength checkout for individual frame member; its safety class may be adopted by reducing
one level.
2.1.5 When combining design according to long-term effect under normal-use limit state, it
shall adopt would-be permanent value act as representative value for the variable load.
Would-be permanent value of variable load is obtained by normal value of variable load
multiply by would-be permanent value factor of load.
Would-be permanent value factor of floor (ground) live load is adopted according to
numerical value in table 2.2.2, table 2.2.4-1 and table 2.2.4-2 of this standard.
4
Would-be permanent value factor of deaerator, industrial water tank, coal, and coal dust in
coal scuttle, tailing classifier and load on pipeline shall all take 1.0.
2.2 Live load on roofing and floor (ground)
2.2.1 When production using, overhauling and constructing/installing the roofing and floor
(ground) of power plant building, load caused by equipment, pipeline, placing of material and
conveyance as well as load of all the equipment, pipeline supporter and hanger on civil
structure shall all be provided by profession of technological design.
2.2.2 When designing according to article 2.1.4 of this standard, load shall take value
according to the following stipulations:
2.2.2.1 When providing load on all the equipments (pipeline) according to technology
profession, floor live load takes value as 2.0 kN/m2.
2.2.2.2 When adopting load on major equipment and pipeline (deaerator, high and low
pressure heater, tailing classifier, industrial water tank, coal scuttle, as well as pipeline such as
main steam, main feedwater, reheat steam, primary air, coal dust system, etc.) provided by
technology profession, floor live load takes value according to floor (roofing) live load for
mainframe calculation in table 2.2.2 of this standard. Table 2.2.2 Live Load on Roofing and Floor (ground) of Main Building in Thermal Power Plant
Normal value
(kN/m2)
Reduction factor for
calculating junior
beam, double T slab
and grid main rib⑧
Single unit
capacity (MW)
No.
Designations
12-125 200-300
Would-be perm
anent value factor
6m≤Spaci
ng of
columns<
9m
9m≤Spac
ing of
columns
≤12m
Reduction
factor when
calculating
major beam
(column)
Floor (roofing) live
load on calculating
main
frame-bent③(kN/m2)
Notices
Firstly Steam turbine house
±0.000m
Site for collective maintenance of basement
top plate① 15—20 25—30 0.5 0.8 0.7 0.7 —
General region of basement top plate 10 10—20 0.5 0.8 0.7 0.7 —
Ground of collective maintenance region 20—30 40 — — — — —
to make calculation according to process unit and structural arrangement conditions.
Transverse frame-bent shall be solved united in conjunction with outer side column of the
main building.
3.1.10 Frame-bent of the main building may adopt plane trussing design diagram, that is make
frame beam and column centerline act as design diagram of frame geometric shape, column
root takes fundamental top surface. When upper prop eccentric to the lower prop, it shall
consider bending moment influence caused by eccentricity.
3.1.11 When calculating transverse or longitudinal frame load, longitudinal coupling-wall
beam, or transverse frame beam may degenerate into freely supported beam. When
calculating corbel strength, its load shall consider continuity of the beam.
3.1.12 When adopting simplified calculation, it may refer to the method in appendix A.
3.1.13 Steam turbine house outer side column of the main building frame-bent and calculated
length of frame column of the oxygen removal bunker bay may be adopted according to table
3.1.13. Table 3.1.13 Calculated length of frame-bent column of the main building
Designations Structure types Frame
direction
Perpendicular
frame direction
Upper prop 2.5Hc When
considering
crane load Lower prop 0.9Hc
Lower prop 2.0Hc
Outer side column of
steam turbine house When not
considering
crane load Lower prop 1.1Hc
Top layer 1.25Hs
Other layers
1.0Hc
Frame column of oxygen Coping 1.25Hc
16
removal bunker bay Rest layers 1.0Hc
Note: Hc is the distance between longitudinal and transverse beam centerline.
3.1.14 For protruding column of outer coal bunker frame and inner coal bunker frame as well
as outer side column of boiler room: when column bottom is regarded as rigid coupling, their
calculated length may be adopted according to table 3.1.14-1.
Calculated length factor μ of protruding column of outer and inner coal bunker frame as well
as outer side column of boiler room may be determined according to formula (3.1.14-1).
μ=αμ0 (3.1.14-1)
Where: μ——Calculated length factor of the column, when calculated value is less than
0.90, it takes μ=0.90;
μ0——Initial calculated length factor of protruding column or outer side
column of the frame, μ0 value sees table 3.1.14-2;
α——Regulation factor, for protruding column of frame: α=1.05, for outer side
column of boiler room: α=1.00 (in the perpendicular frame direction, α=1.00). Table 3.1.14-1 Calculated length l0 of protruding column and outer side column of outer and inner coal
bunker frame
Designations Structure types Frame direction Perpendicular frame
direction
Protruding column
of outer coal bunker
frame
Protruding
column of the
frame
Protruding column
and outer side
column of inner coal
bunker frame
Protruding
column and
outer side
column of
frame
μHc
μHc
Coping 1.25Hc
Rest layers 1.0Hc
Note: Hc is the distance between longitudinal and transverse beam centerline.
Table 3.1.14-2 Initial calculated length factor of protrude column or outer side column of the frame μ0
η1, 2 0 1 2 3 4 5 6 8
μ0 2 1.74 1.56 1.43 1.32 1.24 1.18 1.07
η1, 2 10 12 14 17 20 23 ∞ —
μ0 0.99 0.94 0.89 0.84 0.80 0.78 0.7 —
μ0 value in table 3.1.14-2 is checked by η1,2, η1,2 is parameter of column calculated length,
it may be calculated according to formula (3.1.14-2):
η1,2=2,1
32,11,2
EI
HC (3.1.14-2)
C1,2= kH
EI3
1,2
1,23 (3.1.14-3)
Where: C2,1——Spring stiffness of protruding column or outer side column of two
adjacent frames;
17
I1,2——Moment of inertia of protruding column or outer side column of
frames;
H1,2——Height of protruding column or outer side column of frames;
k——factors, k=0.3. Note: tables in this article and corner connectors 1 and 2 in the formula are correspondent to H1 and H2 in table 3.1.14-1.
3.1.15 When the frame-bent is battened column, it should calculate battened column
according to frame or truss. When making internal force analysis for transverse frame-bent,
battened column in the outer side may also be approximately converted to solid web column,
its moment of inertia may be calculated according to formula (3.1.15) (figure 3.1.15).
Figure 3.1.15 Design Schedule of Reduced Moment of Inertia for Battened Column
2
22Iz
fz
LAI (3.1.15)
Where: Iz——the minimal moment of inertia for the single-limb-column, Iz=12
3zbh
;
Az——Cross-sectional area of the single-limb;
Lf——Middle ordinate of the battened column;
β——Reduction factor, battened column of flat web member β=0.7, battened
column of diagonal web member β=0.9.
3.1.16 Intercolumnar bridging of longitudinal frame should adopt steel structure. Longitudinal
horizontal force may be bear by drawbar and pressure bar or only bear by drawbar. Support
bar shall meet the requirement of pressure bar structure.
3.1.17 When making internal force analysis by adopting plane trussing design schedule,
design value Mb of bearing bending moment of the beam takes bending moment value 1.3 b
away from the column centerline;
Mb may also be calculated approximately according to formula (3.1.17). Design value of
bearing bending moment of the beam shall be no less than 70% of the bending moment at the
column centerline section.
Mb=Mz - Vb3
1 (3.1.17)
Where: Mz——Design value of the beam support bending moment at the column
18
centerline section;
V——Shearing force design value of beam support correspond to Mz;
b——Section height of the column
3.1.18 When making internal force analysis for transverse frame of the main building, it may
adopt design schedule at the node rigid zone.
Rigid zone length in column direction d1=0.25h
Rigid zone length in beam direction d2=0.25b
Where: h——Section height of the beam;
b——Section height of the column
Figure 3.1.18 Design Schedule at the Node Rigid Zone
3.1.19 H-mode sectional frame shall be checked with beam transverse strength and crack
resistance at construction stage.
3.1.20 Jointed form shall be determined according to design feature and execution conditions,
it strives to make simple structure, direct conducting force and credible, fixing and simple
installation as well as easy-to-adjust errors.
In order to ensure integrity of the joint, cement for quadric cast concrete may adopt placement
cement or cement with micro -swelling.
3.1.21 Among columns, it generally adopts tenon joint, the rabbet's length shall not be less
than 20 d (d is diameter of effective bar), and jointed strength shall be calculated according to
load on operational phase.
When calculating bearing capacity in operational phase, it shall take the correspondent
internal force at the jointed section and multiply by joint improvement factor 1.3. By this time,
it may add transverse reinforcement rigid, inside the rabbet, it shall be set with additional
longitudinal reinforcement, and measures to increase strength level of quadric cast concrete.
When condition permitting, columns may be connected with rigidity insert joint. This
kind of joint is applicable to small eccentric compression member (e0≤0.35h0). When
19
eccentricity e0 is larger than 0.35h0, crack resistance calculation is required for the joint
section; its crack width shall not be larger than 0.6 mm.
In order to reduce eccentricity, joint position shall be set in the section with smaller column
bending moment (near to inflection point).
3.1.22 When connection of frame beam and column adopting clear corbel stiff joint of
reinforced-concrete, corbel design may comply with "design specifications for concrete
structure". Vertical force acting on corbel may be calculated according to the following two
phases and being superimposed.
3.1.22.1 Construction phase: beam sets on corbel simply, vertical force acting on corbel is V1,
and it generally includes sole weight of the beam slab.
3.1.22.2 Operational phase: beam and corbel form an integer and it shall consider quadric
crack pouring functions between beam and column as well as shear span ratio's influence of
beam on the action of external load. By this time vertical force acting on corbel may adopt
converted vertical force V2; when beam head is hogging moment, it shall be calculated
according to the following formula:
V2= 2011
1.11
07.0
hbfV c (3.1.22)
λ= 101
Vh
M v
Where: λ——Sectional shear span ratio of the beam support;
V——the maximum shear design value of the beam head in operational phase;
Mv——Correspondent bending moment design value when taking the maximum
shear design value of the beam head in operational phase;
h01——Effective height of the beam head section;
b1——Cross-sectional width of the beam;
fc——Design value of compressive strength at the concrete axle center
3.1.23 Connection of longitudinal coupling-wall beam and column may use joint forms such
as spline, clear corbel and unclear corbel, etc. according to operating requirements and
construction requirements. Structure diagram of spline joint see figure 3.1.23.
Design value of shear bearing capacity of the vertical cross-section for the spline may be
calculated according to the following formula:
V0
30.00.3h
Mnabfv v
ctc (3.1.23)
By this time, it shall also meet the following requirements:
Vh
Mc
v 6.2
13.0
0
Where: c——Improvement factor of shear resistant bearing capacity for spline, it takes
γc= 1.3;
Mv——Design value of bending moment on the spline section corresponding to
V;
20
ft——Design value of tensile strength for the concrete;
bc, hc——Length and height of spline respectively;
n——Tooth number on the same section;
a——Reduction factor of spline strength is adopted according to table 3.1.23;
h0——Effective height of the beam section
Figure 3.1.23, Structure Diagram of the Spline Joint
Table 3.1.23 Reduction Factor a
Tooth number ≤3 4—5 ≥6
α 0.9 0.8 0.7
Connecting piece of the joint and weld shall be determined according to the calculation
of bearing capacity.
3.1.24 In order to ensure certain integrity of the floor structure, it shall connect slabs and
beams.
When adopting trough plate, it may infill with pea gravel concrete in flat seam when
adopting double T plate; it may bury ironworks in advance on slab arris top surface through
short tendon or steel plate welding when there are dynamic load generated by technological
equipment on the floor, slab arris shall connect with built-in fitting on the beam. Generally,
attachment weld length is no less than 60 mm; its height is no less than 6 mm.
3.1.25 Picking ears on the beam of the bearing floor slab should be set along full length of the
beam to bear the concentrated load transferred by the slab arris or junior beam. Under the
action of that load, calculated width of the picking ears may be determined according to the
following formula (figure 3.1.25):
21
Figure 3.1.25 Design Schedule of Picking Ears
Picking ears of rectangular section
b0=b+3as (3.1.25-1)
Picking ears of trapezoidal section
b0=b+2.5as (3.1.25-2)
Where: b——Bearing width of slab arris or junior beam;
s——Distance from load point to picking ears root, it generally takes 30c
cs ;
a——Improvement factor of plasticity, it takes a=1.3;
c——Picking length of the picking ears;
c0——Bearing length of slab arris or junior beam
Crack resistance and strength of picking ears may be calculated according to
calculated-width and general corbel, but it shall ensure shear bearing capacity of diagonal
section of the picking ears is larger than bent bearing capacity of the normal section.
3.2 Roofing structure
3.2.1 Roofing structure of the main building may select roof system of syncretic of with
purlin, without purlin and plate beam (roof truss).
3.2.2 Roof truss pattern may select trapezoidal roof truss, through-type roof truss and
single-slope roof truss.
3.2.3 Monitor frame of the main building shall adopt steel structure.
3.2.4 When the span is no larger than 18 m, it may adopt reinforced-concrete roof truss. When
span is larger than or equal to 21 m and less than 36 m, it should adopt prestressed concrete
roof truss or steel roof truss. When span is no less than 36 m, it shall adopt steel roof truss.
3.2.5 When span is no larger than 36m, roof truss may take no account of thermal action.
3.2.6 When calculating roof truss chord, it shall consider additional strain or pressure (for
through-type roof truss) generated by column to roof truss chord, its value should be
determined by calculation. Main building may be arranged with bracket or may be adopted
22
according to the following data:
For the roof truss in the steam turbine house, it may take 5%-10% of the maximal
calculated strain or pressure of the roof truss chord.
For the roof truss in boiler room, it may take 8%-15% of the maximal calculate d strain
or pressure of the roof truss chord.
3.2.7 Roof truss of prestressed concrete may not calculate deflection.
3.2.8 Roof slope of through-type steel roof truss should not be less than 1/10; height at lower
chord flex section of both ends of the roof truss should not be less than half of the midspan
height of the roof truss.
3.2.9 In order to alleviate roofing weight, it should adopt prestress large-scale roof sheathing
for the main building without purlin system if the execution conditions and material permit.
For the main building with purlin system, it may adopt small trough plate, etc.
3.2.10 Weld of each roof sheathing and chord on roof truss chord or monitor frame shall
ensure weld of three strips of welding. When roof span is no larger than 6 m, weld length is
no less than 60 mm, throat thickness is no less than 6 mm; when roof span is larger than 6m,
weld length is no less than 80 mm, and throat depth is no less than 6 mm.
3.2.11 Disposal on steel roof truss and lower lateral bracing
3.2.11.1 Roof truss and lower lateral bracing should generally be set inside the first roof truss
compartment at both ends of the main building or both ends of the temperature expansion
joint zone (figure 3.2.11-1).
Figure 3.2.11-1 Support Disposal of Roof Truss without Scuttle
(a) Upper cord bracing disposal of roof truss ;
(b) Lower chord bracing disposal of roof truss
3.2.11.2 When scuttle set in the second roof truss compartment at both ends of the main
building or both ends of temperature expansion joint zone, roof truss, and lower lateral
23
bracing should general be set in the second roof truss compartment at both ends of the main
building or both ends of temperature expansion joint zone (figure 3.2.11-2).
Figure 3.2.11-2 Scuttle passing through the second Roof Truss Compartment at both ends of the Main
Building or both ends of the Temperature Expansion Joint Zone and Bracing Disposal of Monitor Frame
(a) Upper cord bracing disposal of roof truss;
(b) Lower chord bracing disposal of roof truss;
(c) Upper cord bracing disposal of monitor frame
3.2.11.3 When length of temperature expansion joint zone is larger than 75 m and less than or
equal to 100 mm, it shall set a beam of upper lateral bracing and lower lateral bracing on roof
truss upper chord and lower chord of the roof truss respectively.
3.2.12 Disposal of longitudinal horizontal-bracing of through-type steel roof truss
Inside diameter at roof hatch——0.5m shall be taken as modulus when the inside
diameter is among 2.5~8m; and 1m shall be taken as the modulus when the inside diameter is
larger than 8m. Note: The height of telescope-feed and multi-tube chimneys refers to the height of interior flue pipe.
7.1.2 The quantity of boilers that single tube chimney is matched should be:
One plant unit of 600MW grade;
No more than 2 plant units of 300MW grade;
No more than three plant units of 200MW grade;
No more than four plant units of 100MW grade;
73
No more than six plant units of or under 50MW grade. Note: The quantity of connected boilers may be properly increased when adopted maintainable chimney.
7.2 Chimney calculation
7.2.1 The chimney calculation in power plant shall not only comply with those specified in
this Section, but also shall comply with the current "Code for Design of Chimneys"
(hereinafter referred to as "Code for Chimneys") and the provisions specified in the
corresponding matching codes.
7.2.2 As for the chimney with height exceeding 240m, the safety coefficient of the strength
calculation of tunnel wall and the stress calculation of horizontal cross-section in operational
phase should be increased by 10%.
7.2.3 The appended bending moment ΔMi of chimney generated by the wind or earthquake
effects may be calculated according to the following equation (see Figure 7.2.3 for design
schedule).
Figure 7.2.3 Design Schedule for Appended Bending Moment of Crosssection
n
ijijji uuGM
1
)( (7.2.3)
Where Gj——Weight of material particle (the vertical earthquake force shall be added when
74
considering the vertical earthquake);
μj, μi——Ultimate horizontal displacements at jth and ith material particles.
When calculating the horizontal displacement of material particle, the influence of
sunlight temperature difference and foundation inclination on displacement shall be counted
in simultaneously.
7.2.4 The design of the flue opening of chimney in power plant shall not only comply with the
relevant provisions of "Code for Chimneys", but also shall abide by the conditions specified
in Annex E.
7.3 Measures for controlling the width of longitudinal cracks on chimney
7.3.1 When recalculating the circumferential reinforcement stress at vertical cross-section of
tunnel wall under temperature effect according to the "Code for Chimneys", the structural
safety factor should be increased by 15%.
7.3.2 The tunnel wall of the chimney with height exceeding 120m should adopt bifacial
reinforcements. By this time, if the steel reinforcements at inner side are set according to the
structure, the minimal reinforcement quantity is:
Vertical reinforcement——The minimum diameter is 10~12mm and the maximal space
is 500mm;
Circumferential reinforcement——The minimum diameter is 8~10mm, the maximal
space is 250mm and is not larger than tunnel wall thickness.
7.3.3 The design of flue gas temperature shall take the probable maximal flue gas temperature
value in the whole service life of chimney and shall take such factors as the fume temperature
variation changed or resulted by the abnormal operating condition of boiler and dedusting
equipments.
7.3.4 When adopting the brickwork inner lining, the mortar joint shall be compacted and
straight joint shall be avoided or reduced, the water absorption of brick shall be low, and the
density shall be decreased greatly with condition that the brick tag number is not less than No.
100 with a view to improving the heat-insulating performance.
7.3.5 The chimneys in power plant shall not adopt the occluded air layer as the
thermal-protective coating. Requirements on heat insulating materials are: Good integrity,
uneasy to be broken or deformed, loose and low water absorption, certain strength, and be
convenient for construction.
7.3.6 The principles for determining the thermal conductivity coefficient of materials:
7.3.6.1 The thermal-protective coating shall adopt the thermal conductivity coefficient value
at the water saturation state:
λ=1.25[λ0+ρ(0.5-λ0)] (7.3.6)
Where λ0——Thermal conductivity coefficient of thermal-protective coating materials at dry
state;
ρ——Water absorption (volumetric proportion) of thermal-protective coating materials at
saturated state.
In equation (7.3.6), (0.5-λ0)=0 when (0.5-λ0)≤0. Note: When adopting materials of hydrophobicity, the thermal conductivity coefficient of thermal-protective coating
materials may be calculated according to the practical water absorption.
75
7.3.6.2 The thermal conductivity coefficient of tunnel wall shall be taken the value at dry
state.
7.3.6.3 The thermal conductivity coefficient of the inner lining of brickwork shall take the
leakage influence of fluegas in brickwork joint into consideration. The value may be thermal
conductivity coefficient of brick being multiplied by the correction coefficient: As for the
inner lining of half bat thick, the correction coefficient is 1.67; as for the inner lining of one
brick thickness, the correction coefficient shall be 1.25 (the forementioned correction
coefficient shall be multiplied by 0.80 as for the section where the fluegas in chimney is of
negative pressure).
7.4 Corrosion resisting measures of chimney
7.4.1 The fluegas in the following conditions are corrosive fumes:
7.4.1.1 The sulfur content in coal is high and the scaling index kc>0.5~1.0.
kc value shall be supplied by the technology department, which is
ORA
Sk
xy
y
c
100 (7.4.1)
Where Sy, Ay——Separately the percentages of the sulfur and dust contents in coal;
∑RxO——Percentage of the total content of basic oxide in the dust content in coal.
∑RxO=CaO+MgO+Na2O+K2O
7.4.1.2 The sulfur content in coal is not high, but after the humidifying with wet cap collector,
the flue gas temperature is less than or close to the dew-point temperature of flue gas.
7.4.2 See Table 7.4.2 for the classification of the corrosiveness of flue gas on chimney
structure. Table 7.4.2 Gradation Table of Corrosive Flue Gas
Corrosiveness index kc of flue gas Type of dust catcher Flue gas
Gradation >2.0 1.5~2.0 1.0~1.5 0.5~1.0 Wet type Dry type
— — — —
— — — — Strong
— — — —
— — — —
Intermediate
— — — —
76
— — — —
Weak
— — — —
Note: When setting with desulfurization plant, the corrosiveness grade of flue gas on chimney may be considered by
reducing the grades in the above table by one grade.
7.4.3 The following factors shall be considered when selecting the corrosion resisting
measures of chimney:
7.4.3.1 Corrosiveness grade of flue gas
7.4.3.2 Possibility that the flue gas is of positive pressure operation in chimney.
7.4.3.3 The total capacity size of the matched generating unit of each chimney and the
importance of the generating unit in power system.
7.4.4 When discharging strong corrosive flue gas, the multi-tube or telescope chimney
structures should be adopted. Namely, the load bearing outer tube and inner tube for
discharging fume are separated to make the stressed structure of outer tube do not contact
with the strong corrosive flue gas. By this time, the inner tube for discharging fume shall be
composed of acid-proof materials.
7.4.5 When discharging weak corrosive fume, the anti-corrosive single-tube chimney
structure may be adopted. By this time, the following anti-corrosive measures shall be
adopted based on the traditional single-tube chimney:
7.4.5.1 The acid-proof lining and acidproof heat insulating materials shall be adopted.
7.4.5.2 The compactness of inner lining structure shall be strengthened for preventing or
reducing the leakage of flue gas.
7.4.5.3 When the inner lining structure can not guarantee the leakage of flue gas, the internal
surface of outer tube shall be adopted with anti-corrosive insulating layer, and the
compactness of the reinforced concrete outer tube shall be improved.
7.4.6 When discharging the medium corrosive flue gas, according to the matching unit
capacity size of chimney and its importance in power system, both the multi-tube or telescope
chimneys and the anti-corrosive single-tube chimney may be adopted.
7.4.7 The operation of flue gas in positive pressure has strong accelerating effect on the
corrosion of chimney, hereby, it should be avoided possibly. By this time, such methods as
cooperating with the technological specialty, improving the shape of or flue pipe, setting flue
gas diffusion head at the chimney top, reducing the flue gas flow velocity and the frictional
resistance of flue gas shall be adopted to make the flue gas be of negative pressure along the
chimney height.
7.4.8 All the positions on the chimney where the flue gas may dew shall be adopted with
measures to prevent the flowing and accumulating of acid liquor.
7.4.9 The corrosion reaction of flue gas at chimney top from the cover shall be taken into
consideration.
If short chimneys exist nearby, the corrosive influence of the fume emission from short
chimney on the external surface of tall chimney shall be noticed.
77
7.5 Chimney structure
7.5.1 When the tunnel wall adopts bifacial reinforcements, the circumferential reinforcements
at internal and external layers shall be separately bonded with the longitudinal reinforcements
at internal and external rows into internal and external mat reinforcement, the circumferential
reinforcements should be around outside the longitudinal reinforcements. When the diameter
of the longitudinal reinforcements at internal and external rows is larger than 18mm, the
internal and external mat reinforcements shall be connected with transverse lacing wires.
Generally, the diameter of lacing wire is not less than 6mm, they shall be of staggered
arrangement with vertical and horizontal space at 500~600mm, and be knotted with
longitudinal reinforcements at it two ends.
7.5.2 As for the chimneys constructed in the regions with fortification intensity at or above 7
grades, the longitudinal reinforcements shall be connected by welding. The longitudinal
reinforcements of other chimneys may be welded or overlapped when the diameter is not
larger than 18mm, and shall adopt soldered joint when the diameter is larger than 18mm.
7.5.3 The tube body is corbelled out with the corbel that is used for supporting the inner lining,
and should be poured together with the tube concrete at one time.
7.5.4 The chimney surface shall be coated with aerial signal coloration, the painting initial
elevation may be higher than the roof by 10~20m, and a larger number of chimneys in the
plant shall be painted with same initial elevation with same type.
7.5.5 When setting with two or more than two flue openings, the chimney should be set with
fume-cutting wall in it, and the wall height shall be 0.50~0.75 times of the open height of
flue.
7.5.6 The dust collecting platform should be set at the bottom of flue opening, and the dust
load of the platform see Table 7.6.7.
7.5.7 The access ladder, signal platform, hand rail, connection board, downlead, and bolts of
the chimney shall be galvanized or be adopted with the atmospheric corrosion protection steel
products. The needle tube of lightning arrester (or ring lightning protection strip) shall be
stainless.
7.6 Flue
7.6.1 The flue may adopt sidewall of reinforced concrete frame structure as the brick filler
wall or may also adopt reinforced concrete box structure. When the single-machine capacity
is at or above 300MW, the steel flue should be adopted.
Requirements on flue structure are small structural vibration with flue gas action, smooth
air current moderate flue gas resistance, good airtightness, anticorrosive and few accumulated
dust.
7.6.2 The civil work and technological specialities shall be closely cooperated to jointly get
done with the arrangement of flue and the selection for the sectional dimension of flue:
7.6.2.1 Each suction fan should be set with independent flue, and should not adopt bus flue.
7.6.2.2 The variation in the crosssection of flue shall be moderate to avoid the sharp turning
of gas flow and the rapid change in the flue gas flow velocity and prevent flue gas from
78
producing eddy zone.
7.6.2.3 The rational flue gas flow velocity should be larger than 8m/s when adopting the dry
dust separator and should be larger than 12m/s when adopting wet dust catcher.
7.6.2.4 Generally, the space between temperature expansion joints of should not be larger than
25m.
7.6.3 In the design of flue, it shall consider that the flue gas pressure shall not be less than
±0.5kN/m2.
7.6.4 The flue shall be with insulation measures to make the temperature difference inside and
outside the flue structure be limited at certain scope:
Brickwork of masonry flue——The internal and external temperature difference shall
not exceed 40℃ (1.5 times of the thickness of brick) or 60℃ (thickness of one brick).
Reinforced concrete top plate or bottom plate of reinforced concrete flue and brick
flue——Internal and external temperature of plate shall not exceed 40℃.
7.6.5 The partial heated temperature of the concrete structure of flue shall not exceed 100℃.
7.6.6 The flue shall be set with inner lining that is featured of such performances as high
temperature resistance, acid resistance, abrasion proof and protection of thermal-protective
coating.
7.6.7 The dust load at the bottom plate of flue see Table 7.6.7. Table 7.6.7 Dust Load on the Dust Collecting Platform of Chimney and Bottom Plate of Flue
Single-machine capacity (MW) ≥200 ≤125
Dedusting mode Dry type Wet type Dry type Wet type
Bottom plate of flue 10 15 15 20 Load
kN/m2 Dust collecting
platform plate of
chimney
25 30 30 35
Note: When the dust collecting platform is set with flue gas guiding slope structure, the dust load may be appropriately
decreased according to the table above.
7.6.8 The wall structure of flue shall take the side pressure produced by the collected dust on
bottom plate into consideration. When calculating this side pressure, as for the straight wall,
1~2 m from the thickness of dust layer may be taken; a for the arc-like wall and diagonal wall,
2~4m from the thickness of dust layer may be taken
7.6.9 The corrosion resistance requirement of flue may be referred to the Section 7.4.
8 Pipe support
8.0.1 According to the function, stressing and structural style, the pipe support is classified
into fixed pipe support, guiding pipe support, and slide pipe support. See Figure 8.0.1 for the
arrangement schematic diagram of pipe support.
79
Figure 8.0.1 Schematic Diagram for Arrangement of Pipe Support
Fixed pipe support: The pipe support may be treated as the fixed supporting point of
pipeline both in the longitudinal direction (along pipeline direction) and in the transverse
direction (perpendicular to pipeline direction), the fixed pipe support hereby shall be with
adequate rigidity to assure the stableness of piping system.
Slide pipe support: The pipeline passes through pipe carrier in longitudinal direction and
transverse direction and may slide or roll on column or crossbeam, and generally has small
stressing.
Guiding pipe support: The pipeline is same as the slide pipe supporting longitudinal
direction and may be restricted for its transverse deflection in transverse direction.
8.0.2 The slide and guiding pipe supports may be designed into the rigid, flexible and semi-
articulated pipe supports.
The pipelines on rigid pipe support and flexible pipe support all may be adopted with the
slide or rolling pipe carrier. The connection of lower end of column and the foundation shall
be semi-articulated along the longitudinal direction and be fixed along the transverse
direction.
8.0.2.1 The rigidity of rigid pipe supporting longitudinal direction is large, the displacement is
small, and the friction force acting on pipe support shall comply with the following equation,
the horizontal force of pipe support shall be calculated as Fm.
323
H
EIuF
FF
f
fm
(8.0.2-1)
Where Fm——Friction force of pipeline, which is supplied by technology;
fF ——Rebounding force of the displacement of pipe support;
zu ——Deformation value of drive pipe, which is supplied by technology;
EI——Support rigidity, in which E is elastic modulus, I is inertia moment, and the
support rigidity shall be 0.85EI for reinforced concrete column;
H——Support height (distance from the bottom of the pipe carrier of drive pipe to the
top surface of foundation).
80
The rigid pipe support is applicable to the pipe support of the pipelines with small weight,
large deformation and small height.
8.0.2.2 The rigidity of flexible pipe supporting longitudinal direction is small, the
displacement of pipe support is able to meet requirement on deformation of drive pipe, the
following equation shall be complied with, and the horizontal force of the pipe support shall
be calculated as fF .
fm FF ≥ (8.0.2-2)
The flexible tube support is applicable to the pipe support of the pipelines with large
weight, small deformation and large height.
8.0.2.3 Semi-articulated pipe support: The socle of semi-articulated pipe support shall adopt
incomplete articulation structure along the longitudinal direction, the displacement of pipe
support and the deformation of drive pipe are same, the gradient of displaced pipe support
shall comply with the following equation, and the rebounding of the displacement of pipe
support is ignored.
0.02≤ H
uz (8.0.2-3)
The semi-articulated pipe support is applicable to the pipe support of the pipelines with
large weight and the drive pipes with deformation complying with the gradient requirement of
pipe support.
8.0.3 According to the difference in functions of pipelines on pipe supports, the pipelines on
pipe supports are classified into drive pipe non-drive pipe. The pipeline has controlling action
on the operating condition of pipe support is named as drive pipe; other pipelines are named
as non-drive pipe. The drive pipe shall be arranged near to the center of pipe support, and the
conditions for selecting drive pipe are as follows:
8.0.3.1 Rigid pipe support: The pipeline with largest weight among pipeline shall be taken as
the drive pipe.
8.0.3.2 Flexible pipe support: The pipelines with weight ratio a not less than 0.7 among the
pipelines shall be taken as the drive pipe.
n
i
z
G
Ga
1
(8.0.3-1)
Where iG ——Weight of pipeline;
n——Quantity of pipelines;
zG ——Gravity load of drive pipe, several pipelines of normal temperature may be
regarded as one drive pipe when calculating the zG .
When a is less than 0.7, the pipeline with lesser deformation value zu shall be taken as
the drive pipe. Articulated pipe carrier shall be adopted with the technological approval. By
81
this time, the displacement value u of this pipe supportis equal to the deformation value zu
of this pipeline.
Semi-articulated pipe support: The pipeline with larger weight and with its deformation
value zu meeting the Equation (8.0.2-3) shall be adopted, and the technological approval
shall be obtained.
8.0.4 Load and load effect combination
Permanent load:
The dead load of the pipeline, inner lining, insulating layer and accessories of pipeline,
the deadweight of media in pipeline, the deadweight of pipe support and foundation, and the
load of reserved pipeline.
Variable load:
The transverse horizontal force, wind loads and sleet loads produced by the variation in
pipeline temperature.
The load effect combination shall comply with the "Specifications on the Load of
Building Structure", in which the partial factor of permanent load is:
1.20 When its effect is unfavorable for the structure;
1.00 When its effect is beneficial to the structure;
The partial factor of variable load is 1.40;
The combination factor of load is 0.85.
The calculation of wind loads see Annex F.
8.0.5 Calculation of bearing capacity:
8.0.5.1 The pipe support structure shall have the calculation on internal force according to the
elastic system.
8.0.5.2 The pipe support column shall have the strength calculation according to the
two-direction eccentric compression member. With torque function, the pipe support may
only adopt the structure measure, but the T-pipe support column shall have calculation on
torsion resistant if necessary. The precast element shall have the recalculation on
transportation and hoisting if necessary.
8.0.5.3 With the action of vertical and horizontal loads, the crossbeam of pipe support shall be
calculated according to the two-direction bending member; when the bending moment yM
under vertical load action and the bending moment xM under action of horizontal load
comply with that yM is not less than 0.1 xM , the crossbeam may be calculated as
one-direction bending member.
8.0.6 The computational length of the column of pipe support shall comply with the Table
8.0.6-1 and Table 8.0.6-2.
Table 8.0.6-1 Computational Altitude of the Column of Pipe Support 0H
Structural 1 2 3 4
82
diagram
In
longitudinal
direction
along
pipelineH0
According to
Table 8.0.6-2
1.50H of column at
upper most layer
1.25H of column at
other layers
1.25H 1.00H
In
longitudinal
direction
along
pipelineH0
2.00H
1.50H of column at
upper most layer
1.25H of column at
other layers
1.25H 1.00H
Note: The calculated altitude value in Diagram 2 is only applicable to the conditions that the linear stiffness ratio of beam
and column is not less than 2.
Table 8.0.6-2 Computational Length of Column when it is Single Column in Longitudinal Direction along
Pipeline 0H
Types of pipe support
Computational altitude Fixed pipe support Rigid pipe support Flexible pipe support
Semi-articulated pipe
support
0H 2.00H 1.50H 1.25 H 1.00 H
Note: The value of column length H:
As for the fixed pipe support and rigid pipe support, it is the distance from the top surface of column to the top surface of
foundation. As for other types of pipe supports, it is the distance from the bottom of the pipe carrier of drive pipe to the top
surface of foundation. When the drive pipe is placed on the beam at lower layer, the column at top layer shall
be sHH 00.20 , (Hs is the distance from the bottom of the pipe carrier of drive pipe to the top surface of column).
8.0.7 Allowable length-diameter ratio of the column of pipe support
300 b
H (8.0.7)
Where 0H ——Computational length of column;
b——The dimension of column section corresponding to the 0H direction.
8.0.8 Structural requirements of pipe support:
The crossbeam width is not less than 150mm and the crossbeam height is not less than
200mm. The depth of beam at cantilever end is not less than 150mm.
The minimal edge of column is not less than 200mm.
8.0.9 The groundwork and foundation of pipe support shall be designed according to the
83
related chapters in the "Code for Design of Building Foundation" and shall also comply with
the following requirements:
When being with two-direction eccentric compression:
Foundation of fixed pipe support:
5
1≤
B
eand
A
e yx (8.0.9-1)
Foundations of other pipe supports:
4
1≤
B
eand
A
e yx (8.0.9-2)
When being with uniaxial eccentric compression:
4
1≤
B
eor
A
e yx (8.0.9-3)
Where A and B——Dimension of foundation at bottom margin;
xe and ye ——Excentricity, its value is as follows:
F
Me x
x
F
Me y
x
Where xM and yM ——Design values of bending moment at foundation base along
X-direction and Y-direction;
F——Design value of the vertical force at foundation base.
8.0.10 When the design adopts semi-articulated pipe support, it shall be indicated in the
constructional drawing. In the assembly process, the falsework shall be set and shall not be
demounted until all the pipelines have been installed.
See Figure 8.0.10 for the structure of the socle of semi-articulated pipe support, and the
diameter of the anchor bar of socle may be calculated according to the following equation:
sf
FsMd
ta785.0
5.00
(8.0.10)
Where d0——Thread root diameter of anchor bolt, which is not less than 20mm;
M——Design value of the bending moment that acts on the top surface of
foundation;
F——Design value of the minimal vertical force that acts on the top surface of
foundation at operating condition;
s——Centre distance of anchor bolts;
taf ——Design value of tensile strength of anchor bolts.
Equation (8.0.10) is applicable to the semi-articulation mode showed in Figure
84
8.0.10 and it may be free of this limit if other semi-articulated structures are adopted with
practical experience.
Figure 8.0.10 Socle of Semi-articulated Pipe Support
(a) Dual column (b) Single column
9 Aseismic design
9.1 General provisions
9.1.1 The aseismic design of buildings shall implement the state's guideline that prevention
first in seismic operation. Sum up the experience on all previous earthquake disasters,
treatment in accordance with local conditions, positively adopt the aseismatic measures with
reliable technology and rational economy.
9.1.2 This chapter is applicable to the newly-built or extended power plant buildings with
fortification intensity among degree 6 and 9. Note: Generally, this stipulation skips such words as "fortification intensity", as the "fortification intensity" is degree 6 is
named as "degree 6" for short.
9.1.3 The fortification intensity of power plant buildings shall be determined according to the
documents (drawings) examined, approved and awarded according to the state's due authority,
and generally, the basic intensity may be adopted. And it shall be adjusted and determined
according to the following principles.
9.1.3.1 The regions with antiseismic disaster prevention planning may carry out the
earthquake protection according to the approved earthquake protection zoning (fortification
intensity or design earthquake motion parameter).
9.1.3.2 The earthquake effect shall be calculated according to the local fortification intensity
85
(excluding the power plant in the region of degree 6 specified by the state shall be fortified by
one more degree).
9.1.3.3 The main manufacturing buildings in the important power plants with planning and
design capacity of 800MW or single-machine capacity at or above 300MW, as well as the
power supply buildings in the lifeline projects of key antiseismic cities shall be of the
first-grade buildings (which are equivalent to second-grade buildings specified in "Code for
Seismic Design of Building").
9.1.3.4 Except those specified in the Sub-section 9.1.3.3 of this section, the main
manufacturing buildings and buildings in continuous production run in general power plants
as well as the public buildings and important material storages shall be of the second-grade
buildings (which is equivalent to the third-grade buildings specified in "Code for Seismic
Design of Building").
The auxiliary buildings shall be of the third-grade buildings (which are equivalent to the
buildings of Grade D specified in "Code for Seismic Design of Building").
The buildings that have no influence on manufacturing, cause no greater loss and are
easy to be repaired may not be fortified.
9.1.4 The fortification intensity of the aseismatic measures of each building in power plant
may be adjusted according to Table 9.1.4.
86
Table 9.1.4 Adjustment Table for Fortification Intensity of the Aseismatic Measures of Buildings in Power
Plant
Important power plant General power plant
Local fortification intensity Local fortification intensity
Local fortification intensity Local fortification intensity
9 8 7 6
Building name
(II) Auxiliary production workshop and
structures 6 7 8 9
9 8 7 6 Oil purification room 6 6 7 8
9 8 7 6 Open-air oil storage 6 6 7 8
9 8 7 6 Acetylene station 6 7 8 9
9 8 7 6 Hydrogen production station 6 7 8 9
9 8 7 6 Mechanical workshop 6 7 8 9
9 8 7 6 Separate machine and boiler overhaul room 6 7 8 9
9 8 7 6 Precise material storage or
dangerous cargo warehouse 6 7 8 9
8 7 6 6
Material
storage General material storage 6 6 7 8
9 8 7 6 Compressor plant 6 7 8 9
9 8 7 6 Pipe support 6 7 8 9
9 8 7 6 Lightning arrester 6 7 8 9
Important power plant General power plant
Local fortification intensity Local fortification intensity
9 8 7 6
Building name
(III) Appurtenant structures 6 7 8 9
9 8 7 6 Engine room 6 6 7 8
9 8 7 6 Coal transporter warehouse 6 6 7 8
9 8 7 6 Motor depot 6 7 8 9
9 8 7 6 Fire engine house and fire station 6 7 8 9
9 8 7 6 Office building 6 7 8 9
9 8 7 6 Canteen 6 7 8 9
9 8 7 6 Overbridge 6 7 8 9
9 8 7 6 Duty and refreshment building 6 7 8 9
9 8 7 6 Gate chamber 6 7 8 9
6 6 6 6 Enclosing wall at plant site 6 6 6 6
6 6 6 6 Bicycle shed 6 6 6 6
6 6 6 6 Toilet at plant site 6 6 6 6
Notes: 1. The division between important power plant and general power plant is determined according to the "Code for
88
Seismic Design of Electric Power Installations".
2. Those improved with fortification intensity in the table are all equivalent to the second-grade buildings specified
in "Code for Seismic Design of Building", their aseismatic measures shall be fortified by adjusting the intensity
according to the table, and the anti-seismic construction measures may not be improved when the building site is
of I type site;
3. In the table the buildings that has adopt antiseismic measures by reducing one degree shall not reduce the
fortification intensity for other reasons, and those that has not reduced the fortification intensity may adopt
anti-seismic construction measures by reducing one degree according to the original fortification intensity, but the
fortification intensity shall not be less than degree 6.
4. In the table, the buildings not improving the fortification intensity are equivalent to the third-grade buildings
specified in "Code for Seismic Design of Building". The buildings with fortification intensity reduced by one
degree are equivalent to the buildings of Class D as specified in "Code for Seismic Design of Building".
9.1.5 The antiseismic grade of the frame structure of power plant buildings shall be divided
according to Table 9.1.5 in accordance with the fortification intensity, structure type and
height of the earthquake resisting wall in framework. Table 9.1.5 Antiseismic Grade of Frame Structure
Main workshop
Frame structure
Main workshop
Framework-earthquake
resisting wall structure
Main control
building
Power distribution
unit building
Coal
transpor
ting
trestle
Pipe
support
Rating
Height
(m)
Ratin
g
Height
(m) Framewo
rk
Earthqua
ke
resisting
wall
Rating Rating Rating
≤25 4 ≤50 4 3 6
>25 3 >50 3 3 3 3 3
≤35 3 ≤60 3 2 7
>35 2 >60 2 2 2 3 3
≤35 2 <50 3 2 8
>35 1 50~80 2 2 2 2 2
≤25 2 1 9 (Note 2)
>25 1 1 1 1 1
Notes: 1. The outside column of main workshop shall comply with the relevant provisions on monolayer industrial factory
buildings specified in the Chapter 8 of "Code for Seismic Design of Building";
2. When the fortification intensity is 9, the structure of main workshop framework shall not be adopted until after
justifying the reliability of its seismic performance according to the structure conditions, and the antiseismic
grade is Grade 1.
3. When the antiseismic grade is Grade 1, the building still needs to be fortified by improving one grade, the
antiseismic grade shall be still Grade 1.
4. The height listed in the table refers to the height from the outdoor ground to the cornice;
5. This table is applicable to the casted-in-site or assembly compound reinforced concrete structures;
6. The column of framework-earthquake resisting wall structure is applicable to the framework-antiseismic support
Tpyes
Antiseismic
gradeFortification
intensity
89
structures;
7. The fortification intensity listed in the table refers to fortification intensity adjusted according to the importance
of buildings;
8. When the main workshop framework has aseismic design on the joint of framework and the crosssection of
elements according to those specified in the second section of Chapter 6 in "Code for Seismic Design of
Building", the antiseismic grade of framework may be adopted according to the un-adjusted antiseismic
protection grade.
9.1.6 When the antiseismic grade of framework is Grade 1, the reinforced in- situ concrete
framework shall be adopted.
9.2 Subgrade and foundation
9.2.1 In the regions of degree 8 and 9, the standard value for the static bearing capacity of
active zone of foundation are separately less than 100 and 110kPa. The weak soil layer with
average shearing wave velocity less than 140m/s shall be adopted with appropriate aseismatic
measures according to the importance of buildings.
9.2.1.1 The main workshop, chimney, main control building, coal transporting in the
first-grade buildings should be adopted with measures such as pile foundation, deep
foundation, as well as excavating the weal soil layer to decreasing the differential settlement
that may be caused by earthquake.
9.2.1.2 The second-grade buildings with small load may partially eliminate the settlement that
may caused by earthquake, as excavating part of the weal soil layer when the reinforcement
condition is unavailable, the following measures may be adopted:
(1) Reducing the static bearing capacity of subgrade.
(2) Reducing the load of foundation and adjusting the basal area of foundation.
(3) Strengthening the integrity and rigidity of foundation.
(4) The superstructure should not adopt the structural shape that is sensitive to the
differential settlement.
(5) When reinforcing the foundation by adopting such methods as displacement of soil,
tamping and compacting, the reinforcement depth and width shall meet the requirement on
the bearing capacity and deformation of subgrade.
9.2.2 Generally, the first and second-grade buildings shall avoid adopting the untreated
liquefiable soil layer as the supporting course of natural foundation. The judgment and
treatment of liquefiable foundation soil shall comply with the relevant provisions specified in
"Code for Seismic Design of Building".
9.2.3 According to the types and fortification intensity of buildings, the antiseismic types of
pile foundations should be determined according to Table 9.2.3. Table 9.2.3 Types of the Seismic Performances of Pile Foundation
Types of buildings
Fortification intensity 1 2 3
90
6 and 7
8
9
C
B
A
C
B
A
C
C
B
9.2.3.1 Piles of Class C: They shall meet the structure requirements on general pile
foundations.
9.2.3.2 Piles of Class B: They shall meet all the requirements on piles of Class C, and should
meet the following structure requirements: the pile top shall enter into the grind slab for no
less than 100mm, the hook of hooped reinforcement at pile body is not less than 135°, the
diameter of the hooped reinforcement within 1.20m up and down the soft and hard soil
interface that is at 1/3 of the upper pile body and in scope no less than 5m and the hooped
reinforcement at the pile top are same, their space should be 100mm.
The requirements on each kind of pile reinforcements are as follows:
(1) Filling pile. The length of the steel reinforcement placed at top should not be less than
10 times of the pile diameter. When at soft ground subgrade and collapsible loess subgrade
with complicated stratigraphic fluctuation, the reinforcement at pile body should be extended
to the pile toe. The reinforcement ratio should not be less than 0.4%~0.65%, the small pile
shall be taken with the larger value and the pile with diameter of or above 800mm shall be
taken with the smaller value. Within 1000mm at the upper part of pile body, the space
between hooped reinforcements should be 100mm and the spiral hoop should be adopted.
(2) Precast pile. The critical steel ratio of longitudinal reinforcement is 1%, the diameter
of the hooped reinforcement at pile body within 1.6m at joint of pile top and grind slab shall
not be less than 6mm, and the space shall be 100mm. When the piles need to be extended, the
steel plate welding wheel dresser should be adopted.
(3) Steel-pipe pile. When it is uplift pile, the reinforcement bar amount at pile top should
not be less than the withdrawal resistance of this pile. The minimal reinforcement bar amount
of uplift pile and anchored pile all should not be less than 1% of the concrete cross-sectional
area, and shall meet the uplift requirement.
9.2.3.3 The piles of Class A shall comply with all the requirements on piles of Class B and
shall comply with the following requirements:
(1) Filling pile. The maximal space between hooped reinforcements within 1.2m at upper
part of pile body shall be 80mm and shall not be larger than 8d (d is the diameter of
longitudinal reinforcement). When the pile diameter is less than 500mm, those with diameter
of 8mm shall be adopted; those with diameter of 10mm shall be adopted for other pile
diameters.
(2) Precast pile. The critical steel ratio of longitudinal reinforcement is 1.2%, the
diameter of the hooped reinforcement at pile body within 1.6m at joint of pile top and grind
slab shall not be less than 8mm, and the space shall be 100mm.
(3) Steel-pipe pile. The steel-pipe pile and grind slab are connected; the tensile force
value is equal to 1/10 of the compression resistant capability according to the stretch design.
9.2.4 As for the pile of buildings with earthquake protection, according to tensile
reinforcement requirement, the amount of piles with the main reinforcement at pile body
anchored into the grind slab should comply with the following requirements:
9.2.4.1 When it is of degree 6 and 7, the piles at periphery of grind slab should not be
anchored with at least one row.
91
9.2.4.2 When it is of degree 8, all the piles within scope of grind slab should be anchored. As
for the steam turbine generator pedestal, boiler foundation and chimney foundation with a
large number of piles, at least two rows of piles shall be anchored at periphery of grind slab.
9.2.4.3 When it is of degree 9, all the piles within scope of grind slab shall be anchored.
9.2.4.4 All the piles shall be anchored when the up-pulling force is produced by earthquake
effect.
9.2.4.5 As for the buildings that need to be adopted with aseismatic measures by improving
one degree, the amount of anchored piles shall be considered according to original
fortification intensity.
9.3 Earthquake effect and antiseismic recalculation of structure
9.3.1 Generally, only the horizontal earthquake effect needs to be considered, and may be
separately recalculated at the two main shaft directions of the buildings.
In the following conditions, the building may not have the antiseismic recalculation of
structure:
9.3.1.1 When the sites of degree 6, 7 and 8 are of sites of types I and II, the height shall not
exceed 60m, and the silo body shall be the masonry stack set with steel reinforcement
according to those specified in "Code for Seismic Design of Building".
9.3.1.2 When sites of degree 6 and 7 are those of class I and II, the transverse part at the coal
transporting trestle of reinforced concrete and steel load carrying structures.
9.3.1.3 When sites of degree 6 and 7 are those of class I and II, the column height does not
exceed 10m, the reinforced concrete monolayer buildings with constant height at each span.
9.3.1.4 When sites of degree 6, 7 and 8 are those of class I, the subsurface constructions such
as buried channel, tunnel, ash settling tank and slot-type coal chute.
9.3.2 As for the chimneys of degree 8 and 9, the structures with wide span (the roof truss,
bracket, trestle and overbridge with span larger than 24m) and long cantalever shall be
considered according to worst situation that the horizontal earthquake effect and vertical
earthquake effect act on the structure simultaneously.
9.3.3 Calculation method of horizontal earthquake effect:
9.3.3.1 The base shearing method may be adopted for the structures with height not exceeding
40m, mainly with shearing deformation and even distribution of mass and rigidity along
height, as well as the architectures approximate to single material particle.
9.3.3.2 Except the building structures specified in the first sub-section, the main workshop
and multistory frame without considering the twisting effect of horizontal earthquake, and the
trestlework and chimney of high and low span should adopt modal decomposition response
spectrum method.
9.3.3.3 When it is degree 8, the main workshop with single-machine capacity of 600MW and
the chimney with height larger than 240m shall not only have the calculation on the horizontal
earthquake effect, but also shall have verification on the weak positions of the structure with
time interval analysis method.
9.3.4 When calculating the earthquake effect, the representative value of the gravity load of
building shall be the sum of the standard value for the gravity load of structure, equipment
and element and the variable combination value of loads. The combination value coefficient
92
of each variable load shall be adopted according to Table 9.3.4. Table 9.3.4 Combination Value Coefficient
Load types Combination value
coefficient
Load of general equipments (such as pipeline and equipment supporter)
Mobile load at roof of turbine room
Coal in coal scuttle and the deoxidizer (including gravity load and water weight)
When the main workshop framework is calculated according to the floor mobile load (including the
roof of deoxidation bunker bay) used for calculating the mainframe
Long-term horizontal load (such as tensile force of conductor)
Long-term dynamic load
1.0
Ignored
0.8
0.7
1.0
0.25
Note: The structure mainly bearing wind loads shall be considered for function of wind loads according to "Code for
Seismic Design of Building".
9.3.5 The horizontal earthquake effect on monitor frame and its vertical bracing extruding out
the roof, the detached buildings (control center and switchboard room) in main structure or on
firing floor should be multiplied by the augmenting factor 1.5.
As for the booth and parapet extruding the roof of the top floor of building, their
horizontal earthquake effect should be multiplied by the augmenting factor 3. Note: The partial increased influence on infrastructure shall not be considered.
9.3.6 When the connection points (including anchoring of attachment weld and anchor bar
and the shear resistance, compression and anchoring construction bolts) having antiseismic
recalculation, the earthquake effect should be multiplied by the strengthening coefficient 1.5
(welded connection) or 1.2 (bolted connection).
When the main workshop is of frame-bent structure in transverse direction, the
calculation on the horizontal earthquake effect at head end of roof truss and at fastening piece
of pedestal should take the earthquake effect on the link rod of the column top in this span be
multiplied by the earthquake augmenting factor 2. When recalculating the shearing strength at
the welding seams and bolts at the connection point of roof truss and pillar, the earthquake
effect at each end should be:
9.3.6.1 As for welding, it should be the earthquake effect at link rod of this column top in this
span being multiplied by the augmenting factor 2, and then being multiplied by the
strengthening coefficient 1.5.
9.3.6.2 As for bolted connection, it should be the earthquake effect at link rod of this column
top in this span being multiplied by the augmenting factor 2, and then being multiplied by the
strengthening coefficient 1.2.
9.4 Main workshop
9.4.1 When the horizontal structure of main workshop having shock strength recalculation,
frame-bent structure earthquake resistance may be composed of outside column of turbine
room and framework, and representative framework shall be chosen according to the load or
structural diagram for the internal force analysis.
9.4.2 When the transverse major structure of main workshop having shock strength
recalculation, the following terms of simplification may be made, see Figure 9.4.2-1.
93
Figure 9.4.2-1 Distribution of the Material Particles of Structure
9.4.2.1 The rigidity of non-antiseismic wall shall not be considered, and only its weight shall
be taken into account.
9.4.2.2 The influence of foundation deformation shall not be taken into consideration.
9.4.2.3 The mass of the outside column of turbine room system may be centered on the center
of cantalever at firing floor, the bottom of crane beam and the elevation part of column top,
and the mass of the frame system may be centered on the center of the beams at each floor,
the bottom of crane beam and the elevation part of the supporting point of roof truss.
The mass of the lateral column system of boiler room may be separately centered on
some points from the center elevation of firing floor beams to the column top.
The mass of the vertical structural systems may be centered on the center elevation of
each longitudinal beam and the elevation part at column top.
9.4.2.4 When simply calculating the fundamental period of framework, the mass and rigidity
of the lateral column may be neglected, but the roof mass shall be wholly considered yet
(Figure 9.4.2-2).
Figure 9.4.2-2 Frame Structure Diagram
9.4.2.5 When it is 9 degree, the framework set with coal scuttle should be considered with the
influence of additional bending moment.
9.4.2.6 The axial load ratio of main workshop framework column shall not exceed the
following limitation: 0.8 of the first grade, 0.85 of the second grade and 0.9 of the third grade,
94
9.4.3 The longitudinal constructions such as outside column of turbine room, lateral column
of boiler room and colonnade of the framework of deoxidation bunker bay may be have the
recalculation on aseismic strength according to the single-row colonnade in the simplified
calculation.
9.4.4 The framework-earthquake resisting wall (support) system in longitudinal constructions
should be considered with the team work and shall comply with the relevant clauses specified
in "Code for Seismic Design of Building".
If adopting simplified calculation, it may be according to that the earthquake resisting
wall and antiseismic support bear 100% of the earthquake effect. The framework shall bear
20% of the corresponding earthquake effect in addition. The percentage may be reduced
appropriately when the quantity of colonnades is small, but should not be less than 10%.
The bending moment of the earthquake effect at top floor of longitudinal framework
shall not be less than the seismic bending moment at nay beam, the longitudinal beam shall be
considered with the transferring the horizontal earthquake effect and the framework column
shall be considered with the vertical internal force produced by the horizontal earthquake
effect.
9.4.5 When each colonnade is taken as one antiseismic calculating unit, the gravity load bear
by each longitudinal construction of main workshop all shall be distributed to each colonnade
according to the lever principle.
9.4.6 The width of earthquake-proof joint shall comply with the relevant provisions specified
in "Code for Seismic Design of Building", and the settlement joint and temperature expansion
joint shall comply with the requirements on earthquake-proof joint.
The earthquake-proof joint shall ensure the freed displacement vertically and
horizontally among adjacent buildings. As for the platform at firing floor of boiler and the
coal transporting trestle, when it is degree 7 and 8, the earthquake-proof joint may not be set
along the transverse direction of element for transferring the earthquake effect.
9.4.7 The longitudinal construction of main workshop may be adopted with different
aseismatic measures according to the size of fortification intensity, and may be adopted
according to Table 9.4.7. Table 9.4.7 Aseismatic Measures for Longitudinal Construction of Main Workshop
Fortification intensity Types of aseismatic measures
framework; (f) longitudinal framework on the furnace side
110
Annex C Determination for Gage Length l0 of the Boiler Framework
Frame-Column
Gage length l0 of the boiler framework frame- column may be determined according to
the following formula:
Haa
liu
)]11
(2.01[0 (C1)
Where
au——Rigidity ratio of the beam-column line at the upper node of the calculated column
shell;
ai——Rigidity ratio of the beam-column line at the lower node of the calculated column
shell;
H——For the bottom layer column, it is the distance from the top surface of the
foundation to the top surface of the first layer of beam; while for columns on other layers, it is
the distance between the top surfaces of both upper and lower layers of beam.
Rigidity ratio a (namely au and ai) of the beam-column line at the node may be calculated
according to the following formula:
icici
ibibi
HIE
lIEa
/(
)/(
(C2)
Where
Ebi, Ibi and li——They are elastic modulus, sectional inertia moment and axial line span
of the ith beam respectively;
Eci, Ici and Hi——They are elastic modulus, sectional inertia moment and column height
of the ith column respectively;
Summation sigmonium of formula (C2) shall include all of the beams or columns at the
calculated node. When calculating the sectional inertia moment, impact of reinforcing bars
may not be considered. For bottom layer column, the column and foundation are generally
permanent connected, by then, ai=∞.
Ebi, Ibi, Eci, and Ici of composite structure beam and column shall be valued according to
relevant regulations of "Tentative Specifications for Steel-concrete Composite Structure of
Main Buildings in Thermal Power Plant".
111
Annex D Type-selection, Calculation Diagram and Calculation
Formula of Side Wall of Dumper House and Joint-type Coal
ChuteD1.0.1 Type-selection and calculation diagram of dumper house see Table D1.
Table D1 Type-selection and Calculation Diagram of Dumper House
Calculation diagram No. Type-selection for structure
Portal and frame system Ditch wall and soleplate system
1
2
3
D1.0.2 The type-selection and calculation diagram of joint-type coal chute see Table D2. Table D2 Type-selection and Calculation Diagram of Joint-type Coal Chute
Calculation diagram No. Type-selection for structure
Portal and frame system Ditch wall and soleplate system
112
1
2
3
4
5
6
Headwall, side wall and soleplate may be
calculated by two-way slab or one-way slab
Note: The calculation diagram of portal and frame system may also adopt calculation diagram of combined solution, while
113
the soleplate may also be calculated by other diagrams.
D1.0.3 The side wall calculation formula of the dumper house and joint-type coal chute sees
Table D3. Table D3 the Side Wall Calculation Formula of the Dumper House and Joint-type Coal Chute
H
H11
H
H 22
H
H33 21 n
sin
1m
2
1
I
In
2332 )3(
6
1 K
1
313
1 )]1()1(1[3
1VCm
nn
mK n
2333 3
1VCK fk
KKK
KaKaR
3122
22112
1
2221 K
RKaR
32
H
EIV
Load diagram ai Coefficient
)43(24
41 nn
qHa
)]1()1(1[8
414
2 mnn
mqHa n
)331
2321
23
211 23(
12
qHa
)3()(5
1[
6 13212
2121412
n
m
n
qHa
])1( 2231
)44
51(
30
5
1n
n
qHa
)]1()([30
551
551
2 nnn
m
n
qHa
]463[12
331
2321
23
211
qHa
)(9)(6[12
22
23
2123
312
n
m
n
mqHa
)]2
1(122
3)(4 1
32141
32
331
nn
m
114
231 2
H
Ma
)2(2 332
H
Ma
)43(12
332
23
22
21 m
qHa
)]496(
)1(6)34(2
[12
2332
2232
13212132
22
n
mm
qHa
)2(12
332
23
22
21 m
qHa
])1(
)32(2
1)
54([
62
132
32321213
22
2
n
mm
qHa
H
H11
H
H 22
sin
1m
2
1
I
In 1
311 )]1(1[
3
1VC
n
mK
)]2([6
11
222 K 2
323 3
1VCK
fKKKK
KaKaR
3122
22112
1
2221 K
RKaR
3
2
H
EIV
Load diagram ai Coefficient
)43(24
4111
qHa
)]1(1[8
412
n
mqHa
)44
51(
30
51
11
qH
a
)]1(1[30
512
n
mqHa
115
221
ZH
Ma
)2(2 222
H
Ma
)43(12
321
22
21
21 m
qHa
)]496(2
3[
12321
22
212
31
241
2
2 mn
mqHa
)2(12
321
22
21
21 m
qHa
)5
(6 21
241
3
2 mn
mqHa
Note: 1 Kf is reaction coefficient, generally, Kf=0.8~0.9;
2. C1 and C2 sees the explanation in the end, and its metering unit is kN·m.
Operating instruction of Table D3:
(1) The flexibility factors C1 and C2 may be calculated according to the deflection for the
practical rigidity of ground-based platform plate and coal-feeder platform plate caused under
unit force action (calculation diagram sees Figure D1), with its calculation formula of:
Figure D1 calculation diagram of C1 and C2
116
3
4
01 EI
lKC (m/kN)
4
4
02 EI
lKC (m/kN)
Where
l——Plate span of the platform (m);
E——Elastic modulus of the concrete (kN/m2);
I3——Sectional inertia moment of the ground-based platform plate (m4);
I4——Sectional inertia moment of the coal-feeder platform plate (m4);
Ko——Deflection coefficient under the action of unit force, it may be calculated by
5-span continuous beam formula (look up Table D4); or it may be proximately calculated by
single beam. Table D4 K0 Deflection Coefficient
ni span
position n1 n2 n3 n4 n5
x=0
x=l/2
0
0.00644
0
0.00151
0
0.00315
0
0.00151
0
0.00644
(2) Take x=0 or 2
lx , solve supporting resistance R1 and R2, and at last calculate
bending moment Mj.
117
Annex E Strength Calculation for the Chimney Shaft Opening
E1.0.1 The design of the chimney shaft shall not only comply with relevant regulations of
chimney design codes, but shall also meet the following requirements:
(1) Thickness of the tunnel wall shall comply with the following conditions:
σh=σhw+σhf≤Rat/Kh (E1)
hwhf dr/
r/b
4
1 (E2)
Where
σh——Compressive stress of tunnel wall concrete on both sides of the opening;
σhw——Non-opening section on the opening top, under dead load and wind load actions,
the calculation method for the compressive stress of the marginal concrete in the compressive
region sees "Code for Design of Chimneys";
σhf——Additional compressive stress of tunnel wall concrete on both sides of the
opening;
Rat——Compression resistant design strength of the concrete, see "Code for Design of
Chimneys";
Kh——Safety factor of the concrete, see "Code for Design of Chimneys";
b——Width of the opening;
r——Mean radius of the tunnel wall section at the opening
(2) The surroundings of the opening shall be deployed with additional reinforcement
steel bar, its reinforcing bars disposal scope sees Figure E1, and the reinforcing bars quantity
is as follows:
1) The total area of the additional bar for both sides of the opening may take the
maximum result of the following three formulas:
Ag2=0.65μδbσgwkg/Rgt (E3)
ggt
g kR
Q
r/
r/HA
32
32 (E4)
Ag2=0.65μδb (E5)
2) The total area of the additional bar on top of the opening may take the maximum
result of the following three formulas:
118
Figure E1 Disposal Position of the Additional Bar at the Opening
Symbol descriptions:
θ—Opening semi-angle; δ—Thickness of the tunnel wall; r—Mean radius (at the
elevation in the middle of the hole); d—Bar diameter; b—Width of floss hole; H—Height of
the floss hole
ggt
gb QkbR
HA
8
3 (E6)
gg
hgb k
w
wbA3.0 (E7)
Agb=0.65μ0δ0H (E8)
3) The total area of the additional bar on the lower part of the opening may take the
maximum result of formula (E6) and the following formula:
Agb=0.5μ0δH (E9)
Where
δ——Thickness of the tunnel wall;
b and H——Width and height of the opening;
Rgt and kg——Tensile design strength and safety factor of the steel bar, see "Code for
Design of Chimneys";
Q——Wind shear act on the section on top of the opening;
δ0——Effective height of the tunnel wall;
μ0 and μ——Reinforcement ratio of the circumferential and longitudinal reinforcement,
it is calculated according to the requirements of "Code for Design of Chimneys";
119
σhw and σgw——Non-opening section on top of the opening, under dead load and wind
load actions, the calculation method for the edge stress of the compressive region and tensile
region sees "Code for Design of Chimneys";
4) The four corners of the opening must be set with 45° inclined additional bar, and
steel bar of corners is deployed at least 250mm2 every 100mm by the thickness of the
tunnel wall.
120
Annex F Calculation of Wind Load of the Pipeline Support
F1.0.1 calculation diagram of the monolayer multi-pipeline wind load sees Figure F1 and its
calculation formula is as follows:
Figure F1 Calculation Diagram of Monolayer Multi-pipeline
Dilww szk 10 (F1)
Where
μz——Variation coefficient of the wind pressure height, it is selected according to "Load
Code for the Design of Building Structures";
w0——Basic wind pressure (kN/m2);
l——Pipeline spans; when the pipe-line spans on both sides of the pipe support are
unequal, the average value is taken (m);
Di——Outside diameter of the pipeline, including the insulating layer (m);
μs1——Shape coefficient of the pipeline wind load, it is looked up from Figure F2.
When the pipe diameters are unequal, therein, the shape coefficient μs3 of the maximum
pipe takes 0.6 (when the pipe diameters are equal, shape coefficient of all the pipe takes 0.6),
the rest pipes is down the wind, with the front of the big pipe is s1/D1 or s2 /D2, and its back is
s3 /D3 or s4/D4… and μs1, μs2, μs3 and μs4 are looked up one by one.
When w0D2 is no less than 0.02, μs1 is directly looked up from Figure F2.
When w0D2 is no greater than 0.003, the looked-up value shall also be multiplied by 2.
When w0D2 is within 0.003~0.02, the looked-up μs1 shall also be multiplied by the
improvement factor looked up from Figure F3.
F1.0.2 Calculation diagram of multilayer multi-pipeline wind load sees Figure F4 and its
calculation formula is as follows:
121
Figure F2 Shape Coefficient of Monolayer Multi-pipeline Wind Load
Figure F3 Improvement factor
wki=μ's1wk (F2)
Where
wk——Wind load of some layer of pipeline, it is calculated by formula (F1);
μ's1——Influence coefficient between the upper and lower layers, it is looked up by
122
Figure F5. Namely, μ's2 is looked up by s1/D1 and μ's1 is looked up by s1/D2; in like manner,
μ's3 is looked up by s2/D2 and μ's2 is looked up by s2/D3. Influence coefficient of the middle
layer pipeline is the result of influence coefficients sum of both the upper and the lower layers
subtracts 1.0. D1 is the diameter of the maximum pipe on each layer, si is the clear distance
among the maximum pipes, see Figure F4.
F1.0.3 Wind load of the pipe support is calculated according to the following formula:
Figure F4 Calculation Diagram of Multilayer Multi-pipeline
Figure F5 Influence Coefficient among the Multilayer Multi-pipeline inter-layers
wk=μsμzw0b (F3)
Where
μz and μs——They are variation coefficient of the wind pressure height and the shape
coefficient of the pipe support wind support respectively, they are adopted by "Load Code for
the Design of Building Structures".
b——Width of the windward support (m)
123
Annex G Regulation Factor of Theoretical Calculation Period
G1.0.1 The following building periods calculated according to engineering mechanics theory
is generally adjusted by coefficient less than 1.0:
(1) Main buildings:
1) The transverse frame structure of the main buildings may be 0.8 of the
computation period
2) Longitudinal structure of the main buildings, it may take 0.7 of the computation
period for the pure frame; when earthquake resisting wall or aseismic support is present,
it may not be adjusted.
(2) Monolayer factory building: it is bent consisted of reinforced concrete roof truss and
steel bar coagulated column; when longitudinal wall is present, it takes 0.8 of the computation
period; when there isn't any longitudinal wall, it takes 0.9 of the computation period.
124
Annex H Aseismic Calculation Method of Trestle Transverse
Direction
H.1 The aseismic calculation method for the rigidity deck with the lower extreme of swing
joint (ground impacted end) and others of elastic bearing (Figure H1) is as follows:
Figure H1 system is one degree of freedom, and the formula of its fundamental period (T)
is:
Figure H1 Calculation Diagram of the Rigidity Deck with One End of Swing Joint and others of Elastic
Support
K
JT 2 (H1)
3
3l
g
GJ (H1.a)
n
iii xKK
1
2 (H1.b)
Where
125
J——Total mass second moment of the system;
Kθ——The products between the supports' rigidities and the distance square away from
the origin;
n——Support number;
G——Total gravity loads of the trestle, including: dead load, equipment weight, deck
and roofing live load, and partial support weight above the deck; for partial support weight, it
may be selected by the following principles: when calculating the fundamental period, it is
1/4 of the total weight of the support; when calculating the support earthquake effect, it is 2/3
of the total weight of the support;
g——Acceleration of gravity;
l——Total length of the trestle;
Ki is the rigidity of the ith support peak, u
Ki
1 , u is the support deflection when unit
force acting on the support peak;
xi——The distance from the ith support to the origin.
Earthquake effect of the supports' top is:
Fi=a1niGl' (H2)
n
ti
iii
xK
xK
1
21
(H2.a)
Where
a1——Seismic influence factor is calculated according to "Code for Seismic Design of
Buildings";
ηi——Distribution coefficient of the earthquake effect;
l'——1/2 of the total length l of the trestle;
When the total length of the deck is less than 25m, T = 0.3s, and fundamental period may
not be calculated any more.
H.2 The aseismic calculation method of the elastic supported rigidity deck is as follows
(Figure H2):
Figure H2 Calculation Diagram of Elastic Supported Rigidity Deck
126
Calculation of natural vibration period:
j
T2
D
DFEEj 2
422
(j=1, 2)
D=mJ
E=mKθ+JKy
F=KyKθ-K2
yx
n
iiy KK
1
i
n
iiyx xKK
1
2
1i
n
ii xKK
(i=1, 2…n, n is the support number)
Where
m——Total mass of the trestlework ( g
Gm
, g is the acceleration of gravity, G is the
total gravity load of the trestle, and the calculation of G is identical to that of other elastic
supported rigidity deck with the lower end swinging);
J——Total mass second moment of the trestlework, J=0.083 ml2, and l is the total length
of the trestle;
Ki——Rigidity of the ith support peak u
Ki
1 ;
xi——Distance from the ith support to the trestle mass center; the mass center is the
origin and xi has plus-minus value
Earthquake effect of the supports' top is:
Fji=Ki(Yj+xiθj) (j=1, 2; i=1, 2, 3···n) (H4)
F
TKFKY jyxj
j
(H4.a)
F
FKTK jyxjyj
(H4.b)
Fj=ajyjYjG (generally, Yj=1) (H4.c)
22j
jJmY
mYy
(Generally, Y=1.0) (H4.d)
Tj=ajyjθ'jJg (H4.e)
127
yx
jyj K
mK 2
(when Yj=1.0) (H4.f)
Where
Fj——Normal value of the total earthquake effect of the trestle;
aj——Seismic influence factor of the jth vibration mode, it is calculated according to
"Code for Seismic Design of Buildings";
Tj——Total torsion moment of the trestle
Earthquake effect combination of the supports is:
2
1jjsS (H5)
Where
sj——Earthquake effect of supports when it is jth vibration mode
H.3 The aseismic calculation method of the elastic supported elastic deck is as follows
(Figure H3):
Figure H3 Calculation Diagram of Elastic Supported Elastic Deck
The trestle with elastic deck should make holistic computation by elastically supported
beam-type structure, or it may be calculated with finite-element method or special procedure.
128
Annex I Explanation of Wording in this Code
1. Words used for different degrees of strictness are explained as follows in order to mark
the differences in executing the requirements in this Code.
1) Words denoting a very strict or mandatory requirement:
“Must” is used for affirmation; “must not” for negation.
2) Words denoting a strict requirement under normal conditions:
“Shall” is used for affirmation; “shall not” for negation.
3) Words denoting a permission of a slight choice or an indication of the most suitable
choice when conditions permit:
“Should” is used for affirmation; “should not” for negation.
2. “Shall comply with…” or “shall meet the requirements of…” is used in this code to
indicate that it is necessary to comply with the requirements stipulated in other relative
standards and codes.
129
Additional explanation
Chief development organization: Northwest Electric Power Design Institute
Participating development organizations: North China Electric Power Design Institute,
Northeast Electric Power Design Institute, East China Electric Power Design Institute,
Southwest Electric Power Design Institute, Central Southern China Electric Power Design
Institute, Hebei Electric Power Survey Design Institute, Electric Power Design Institute of
Jiangsu Province, Shanxi Province Electric Power Survey Design Institute, Heilongjiang
Electric Power Design Institute, Shandong Electric Power Design Institute, Henan Electric
Power Survey Design Institute, Hunan Electric Power Survey and Design Institute,
Guangdong Electric Power Survey and Design Institute and Electric Power Construction
Research Institute.
Major drafting staffs:
NI Shiquan, YANG Zonglie, JING Zhihong, YAO Dekang, YU Zhen’an, JIANG Xianchuan,