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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
2 Load........................................................................................................................................ 2
2.1 Basic requirements....................................................................................................... 2
2.2 Live load on roofing and floor (ground) ...................................................................... 4
2.3 Crane load.................................................................................................................. 10
2.4 Wind load shape coefficient........................................................................................11
3 Main building ....................................................................................................................... 14
3.1 Frame (bent) structure................................................................................................ 14
3.2 Roofing structure ....................................................................................................... 21
3.3 Fender structure ......................................................................................................... 29
3.4 Coal scuttle and crane beam ...................................................................................... 31
3.5 Framework of suspensory boiler................................................................................ 35
3.6 Elevator shaft structure of the boilers ........................................................................ 36
3.7 Frame-bent steel structure.......................................................................................... 37
4 Groundwork and foundation................................................................................................. 39
4.1 Fundamental rules...................................................................................................... 39
4.2 Foundation calculation............................................................................................... 40
4.3 Weak foundation ........................................................................................................ 41
4.4 Foundation in mountain area ..................................................................................... 42
4.5 Collapsible loess foundation ...................................................................................... 44
4.6 Foundation ................................................................................................................. 45
4.7 Underdrain ................................................................................................................. 47
5 Dynamic machine foundations ............................................................................................. 49
5.1 Foundations of automobile unit and electric machines.............................................. 49
5.2 Auxiliary machine foundation.................................................................................... 57
6 Fuel buildings ....................................................................................................................... 62
6.1 Coal-fired buildings ................................................................................................... 62
6.2 Fuel oil buildings ....................................................................................................... 71
7 Chimney and flue ................................................................................................................. 72
7.1 General provisions on chimney ................................................................................. 72
7.2 Chimney calculation .................................................................................................. 73
7.3 Measures for controlling the width of longitudinal cracks on chimney..................... 74
7.4 Corrosion resisting measures of chimney .................................................................. 75
7.5 Chimney structure...................................................................................................... 77
7.6 Flue ............................................................................................................................ 77
8 Pipe support .......................................................................................................................... 78
9 Aseismic design.................................................................................................................... 84
9.1 General provisions ..................................................................................................... 84
9.2 Subgrade and foundation ........................................................................................... 89
9.3 Earthquake effect and antiseismic recalculation of structure..................................... 91
9.4 Main workshop .......................................................................................................... 92
9.5 Master control building and distribution equipment building ................................. 100
2
9.6 Coal-shifting trestle.................................................................................................. 102
9.7 Silo........................................................................................................................... 102
9.8 Equipment foundation.............................................................................................. 104
9.9 Pipeline support ....................................................................................................... 105
Annex A Calculation Diagram of Transverse Frame (Bent Frame) ...................................... 108
Annex B Vertical And Horizontal Calculation Diagram of Suspended Boiler Framework .. 109
Annex C Determination for Gage Length l0 of the Boiler Framework Frame-Column ........110
Annex D Type-selection, Calculation Diagram and Calculation Formula of Side Wall of
Dumper House and Joint-type Coal Chute .............................................................................111
Annex E Strength Calculation for the Chimney Shaft Opening.............................................117
Annex F Calculation of Wind Load of the Pipeline Support................................................. 120
Annex G Regulation Factor of Theoretical Calculation Period............................................. 123
Annex H Aseismic Calculation Method of Trestle Transverse Direction.............................. 124
Annex I Explanation of Wording in this Code ...................................................................... 128
Additional explanation .......................................................................................................... 129
1
1 General provisions
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
simplified combination:
1. 1.2Gk+γQiQik+1.3QQk+1.4Qck (2.1.4-1)
1.0Gk+γQiQik+1.3QQk+1.4Qck (2.1.4-2)
2. 1.2Gk+0.85 (γQiQik+1.3QQk+1.4Qck+1.4ωk (2.14-3)
1.0Gk+0.85 (γQiQik+1.3QQk+1.4Qck+1.4ωk (2.14-3)
3. 1.2 (Gk+ψciQik+ψQiQQk+QcG)+1.3Ehk+1.4ψωωk (2.1.4-5)
1.0 (Gk+ψciQik+ψQiQQk+QcG)+1.3Ehk+1.4ψωωk (2.1.4-6)
Where: Gk——Normal value of permanent load;
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 — — — — —
Other leisure ground and trench cover of
reinforced-concrete② 10 10 0.5 — — — — —
1
Steel cover board 2—4 4 0.5 — — — — —
Mesosphere of heater platform — —
Pipeline layer of heater platform④ 4 6 0.7 0.8 — 0.8 —
Heater floor
with low
pressure
High pressure heater platform④ 10 10 0.7 0.8 — 0.8 —
2
Firing floor platform and pedestal platform
of feed pump 15 0.6 0.8 — 0.7 —
3 Mesosphere platform of steam turbine
pedestal 4 6 0.7 0.8 — 0.7 —
Operation of steam turbine house⑤ 4
General region floor slab of heater platform
(including fixed end platform) 8—10 10 0.5 0.8 — 0.7 —
5
Passable platform of gable overhanging at
extension end 4 4 0.5 0.8 — 0.7 —
Floor slab of overhauling region for
turbogenerator and turbine pedestal platform15—20 25—30 0.5 0.8 — 0.7 —
Cantilever platform of A organ timbering⑥ 4 6 0.6 1.0 1.0 — 4
Cantilever platform of B organ timbering 8 10 0.6 1.0 1.0 — 5—6
Steel cover board 4 4 0.5 — — — —
5 Roofing of steam turbine house⑦ 1 1 0.2 1.0 1.0 0.7 0.5—0.7
Secondary Oxygen removal house
6 Auxiliary switchgear
floor
4
(10)
4
(10) 0.8 0.8 0.7 — 3 (6)
Values in the parentheses is only for high
voltage switchgear
7
Floor of ventilation
layer and cable grip
layer
4 4 0.7 0.7 0.7 — 3
8 Floor of operation
(pipeline layer) 6—8 6—8 0.7 0.8 0.7 — 5—6
9
Floor of other
(non-operated)
pipeline layer
4 4 0.7 0.8 0.7 — 3
10 Floor of deaerator
layer① 4 6 0.7 0.7 0.7 — 3—4
11 Roofing of oxygen
removal house 4 (2) 4 (2) 0.4 0.7 0.7 3 (1)
Numerical value in the parentheses is for load
on pipeline without any equipment in that layer.
when constructing and installing, it only
permits scattered and few placing of material
Thirdly Bunker bay
12 ±0.000m Terrace of coal
grinding mill 15 20 — — — — —
13 Operation floor 6—8 6—8 0.7 0.8 0.7 — 5—6
14 Platform of feed transfer 4 4 0.7 0.7 0.7 — 3
15 Floor of coal scuttle layer 4 4 0.7 0.7 0.7 3
16 Floor of belt layer 4 4 0.7 1.0 0.8 3
Floor of nose gearing of
conveyer belt 10 10 0.7 0.7 0.7 6
17
Bunker bay roofing 4 (2) 4 (2) 0.4 0.7 0.7 — 3 (1)
Numerical value in the parentheses is for
load on pipeline without any equipment in
that layer. When constructing and
installing, it only permits scattered and few
piling up of materials of equipment.
18
Guiding cantilever
platforms of non-operated
floor in oxygen removal
house and bunker bay
4 4 0.7 0.8 0.7 — 3
Fourthly Boiler room
19 ±0.000m Terrace and trench cover of
reinforced-concrete 10 10 0.5 — — — —
20 Operation floor 8 8 0.6 0.8 0.7 0.7 6
21 Reinforced-concrete platforms of
non-operated floor of boiler cradle
4
(6)
4
(6)0.5 0.7 0.7 — 3 (4)
Taken-values in the
parentheses is only used for
coping platform
22 Roofing of boiler room⑦ 1 1 0.2 1.0 1.0 0.7 0.5—0.7
23 Roofing of penthouse⑦ 1 1 0.0 1.0 1.0 0.8 —
Fifthly Others
24 Floor of central control room 4 4 0.8 0.8 0.8 0.7 3
25 Machinery room floor and platform in 4 4 0.7 — — 0.7 — Floor load of machinery room is
6
elevator hoistway provided by manufacturer
26 Steel operating platforms of main
building
2
(4)
2
(4)0.5 — — 0.7 1
Taken-value in the parentheses is
for placing heavier spares as
valve during operating
maintenance
27
Reinforced-concrete stairs (including
main steel stair) in oxygen removal
room and bunker bay)
4 4 0.5 — — — —
28 General steel stair in main building 2 2 0.5 —
29
Other manufacturing building roofing
with possible installation implements
and heat insulator piling up
4 4 0.4 0.8 0.7 0.7
Note: ① When hauling dynamo stator in basement top plate of the steam turbine house or hauling deaerator in the floor, its load
on floor (ground) shall adopt provisional solving measures according to practical hauling scheme.
② When applying ±0.000m equipment operating maintenance (maintenance for fan ground and tube mill) in steam turbine
house and boiler room for reinforced-concrete trench cover and channel (including tunnel) of passage parts, it shall make
calculation according to assemble (or equispaced) live load generated practically. Load on underground facility generated by
temporary heavy lift equipment and transportation hoisting passage during the installation shall be solved by adopting
provisional measures.
③ When spacing of columns is less than 9 m; it takes the larger value, when it is within 9-12 m, it takes the smaller value.
④ Floor live load of high/ low pressure heater in the table is also applicable to horizontal heater floor placing in the oxygen
removal house, but they shall consult to load provided by technology.
⑤ Subarea floor live loads of operation in steam turbine house shall be requiring to be marked on the floor.
⑥ It refers to load on platform of mounting and overhauling of rotor when excluding turbine transverse arrangement, when
it requires to bearing rotor in the platform, it shall provide load by technology.
When turbine is disposed longitudinally, it requires installing overhaul platform in turbine operation platform and cantilever
platform A (B) organ timbering. By this time, load on A (B) organ timbering slab arris (or boundary beam) may be
calculated according to 10 kN/m2 (including sole weight of platform).
⑦ Roofing (including penthouse roofing) live load of steam turbine house and boiler room in the table is only applicable to
reinforced-concrete roofing.
⑧ It shall not consider the reduction factor of junior beam (slab main rib) and reduction factor of main beam (column)
simultaneously.
2.2.3 When designing floor constructional element, floor live load may adopt according to
table 2.2.2, but slab arris (junior beam) shall be counted in pipeline and equipment load (not
considering off-the shelf equipment load such as dial and low tension switch tank, etc.)
2.2.4 When there is no specific requirement for processing set-up, roofing, floor (ground) live
load of other production, auxiliary production and outbuilding may be adopted according to
table 2.2.4-1 and table 2.2.4-2. Table 2.2.4-1 Live Load on Roofing and Floor (Ground) of other Production Building
SN Designations Normal value
(kN/m2)
Would-be
permanent value
factor
Reduction factor
of main beam
(column)
Notices
Firstly Main control floor (grid control building and communication building)
1
Floor of main
control room (grid
control room and
communication
room)
4① 0.8 0.7
2 Floor of cable grip 3 0.8 0.7
7
layer
3 Stairs 3 0.5 —
4 Roofing 0.7 0.0 0.7
Secondary 3, 6, 10, 35, and 110 kV indoor-switching arrangement
5 Floor between
buses 4 0.8 0.7
Including isolator
floor
Floor of switch
house
3, 6 and 10 kV
switch house floor 4—7 0.8 0.7
It is provided by
technology when
each block of
switch weight is
larger than 8 kV.
35 and 110 kV
switch house floor 4—8 0.8 0.7
It is provided by
technology when
each block of
switch weight is
larger than 12 kN.
10, 35 and 110 kV
serial switch
cabinet
4 0.8 0.7
It is limited to
each block of
electric appliance
with weight is no
larger than 36 kN.
6
Floor of 110 kV
complete shut-off
combination
electric appliance
10 0.8 0.7
7 Reactor floor
slab② 0.7 0.7
8 Stairs 3 0.5
9 Roofing 0.7 0.0 0.7
Thirdly Coal discharging device building
10
Floor of slot-type
coal chute along
railroad line
10 0.8 1.0
11 Hoist house floor 10 0.7 0.8
12 Scrabble-coal-fee
der hoist house 15 0.7 0.8
Wagon tipper
house
±0.00m floor
(ground) 10 0.7 0.8
Reinforced-concre
te platforms 4 0.7 0.8
13
Roofing 0.7 0.0 0.7
Fourthly Coal store device building
14 Dry coal shed
roofing 0.7③ 0.0
15 Platform of coal
store silo 4—6 0.6 0.8
Fifthly Coal conveyer building
Overhead bridge
for coal conveyer
Floor 3—4④ 0.7 0.6 16
Roofing 0.7 0.0 0.8
8
17 Underground coal
shipper tunnel 3—4④
Transfer point
Floor 1 0.7 0.7
Floor of nose
gearing of
conveyer belt
10 0.7 0.8
It shall be
provided by
technology,
generally, it may
be adopted
according to 10
kN/m2
18
Roofing 0.7 0.8
19
Floor between
ground reception
bunkers
4 0.7 0.8
Sixthly Coal-breaker house
Conveyer belt
layer
Floor 4 0.7 0.8
20 Floor of nose
gearing of
conveyer belt
10 0.7 0.8
It shall be
provided by
technology,
generally, it may
be adopted
according to 10
kN/m2
21 Floor of coal
screen layer 4 0.7 0.8
22 Floor of
coal-breaker layer 10—20⑤ 0.7 0.7
23
Substratum of
coal-breaker
house
4 (10) 0.7 0.8
Numerical value
in the parentheses
is only used when
substratum is
terrace
24
Roofing of
coal-breaker
house
0.7 0.2 0.7
25 Roofing of
lighting house 0.7 0.0 0.7
Seventhly Chemical water treatment house
26 Floor of each
layer 3 0.5 0.8
It shall be
provided by
technology,
generally, it may
be adopted
according to 3
kN/m2
27 Testing laboratory 3 0.5 0.8
28 Stairs 3 0.5
29 Roofing 0.7 0.0 0.7
Eighthly Ash pump house
30 Floor 10 0.7 0.7
31
Cantilever
platform of article
entering parts
20—30 0.5 0.7
9
32 Other cantilever
platforms 4 0.7 0.8
33 Roofing 0.7 0.0 0.8
Ninthly Pneumatic ash removal building
34 Operation floor 4 0.7 0.7
35 Floor of ash
bucket layer 4 0.7 0.7
36 Roofing 2 0.4 0.7
Tenthly Trench cover
37 Indoor trench
cover 4 0.5
When there is
installation repair
load, it shall be
adopted according
to actual load.
38 Exterior trench
cover 4⑥ 0.5
When there is
installation repair
load, it shall be
adopted according
to actual load.
① When setting up relay bungalow, its floor live load is adopted according to the taken-value of main control room. When
cable in cable floor is suspended on floor slab of main control room or relay bungalow, it shall be considered according to
actual load.
② Floor (ground) live load of reactor is provided by technology.
③ When dry coal shed roofing adopting light roofing as asbestos shingle, corrugated iron and fibreglass tile, etc., its roofing
live load shall be adopted according to 0.3 kN/m2.
④ When belt width is 1.2-1.4 m, live load of trestle bridge floor is adopted according to 4 kN/m2 generally; when belt width
is larger than 1.4 m, it shall be considered as actual load.
⑤ Coal-breaker house frame is combined according to the following two load effects and designed as the most unfavorable
combination among them:
a. When it is combined according to installation conditions, floor live load and reduction factor of main beam (column) is
adopted according to numerical value in this table, live load itemize factor takes 1.3;
b. When it is combined according to operating maintenance condition, coal-breaker load is equipment standard load
multiply by dynamic factor plus relevant floor live load (4kN/m2), equipment and floor load itemize factor takes 1.3.
⑥ Numerical value in the table is only for trench cover basset. When trench cover is inearth, it shall not only consider
overburden layer load, but also adopt possible load according to traffick on the ground and piling up material as well as
reality, but it shall not be less than 4 kN/m2.
Table 2.2.4-2 Roofing, Floor (Ground) Live Load of Auxiliary Production and Outbuilding
SN Designations
Normal
value
(kN/m2)
Would-be
permanent value
factor
Reduction factor of
main beam
(column)
Notices
1
Production office building
(overhaul compartment in the
building)
4 (4—8) 0.7 0.8
2 Administration building 2 (3—5) 0.5 0.8
Numbers in parentheses
are for archives
Material storage and center
maintenance depot
Ground 10—15 — —
It may adopt floor
according to practical
situation
Floor 8 0.8 0.8
3
Roofing 0.7 0.0 0.8
10
Overbridge of main building to
buildings
Floor 3 0.7 0.9 4
Roofing 0.7 0.0 0.9
Note: 1. Live load of life welfare building and its would-be permanent value factor are stipulated according to "Load
Specifications for Building Structure"
2. When designing production office building, it shall arrange the overhaul compartment with heavy piece
overhauling within ±0.000 m terrace live load be adopted according to 8 kN/m2. Floor shall be disposed in the
overhaul compartment with lighter equipment (thermodynamical instrument and electrical service compartment,
etc.); its live load may be adopted according to 4 kN/m2.
2.2.5 Roofing of main building and other production, auxiliary production and outbuilding
may not consider dust load.
2.2.6 Power plant with unit capacity is larger than 300 MW shall decide its taken-value of
roofing and floor (ground) live load according to practical situation.
2.3 Crane load
2.3.1 Crane in steam turbine house, boiler room, grey paddle pump room, maintenance depot,
overhaul compartment and induced draft fan, etc. shall be designed according to light-duty.
Bridge type clamshell crane of bunker coal and ash removal building shall be designed
according to heavy-duty.
2.3.2 Vertical load and horizontal load of main building crane shall be adopted according to
the following stipulations:
2.3.2.1 When there is a set of crane in steam turbine house, crane load shall be adopted
according to “load specifications for building structure".
2.3.2.2 When there are two sets of cranes in the steam turbine house, crane load is adopted
according to the following stipulations:
(1) When calculating crane beam and its support bracket, vertical load and horizontal
load shall both be considered according to load-lifting capacity of the two sets of cranes, but
not consider load reduction factor of crane.
(2) When calculating transverse frame-bent in the main building, vertical load of the
crane is considered according to load-lifting capacity of one set of crane, the other set of
crane only considers sole weight function of itself.
Transverse horizontal load of the crane only considers load-lifting capacity of one set of
crane.
(3) When calculating longitudinal frame in the main building, longitudinal horizontal
load of the crane shall be considered according to two sets of cranes with simultaneous and
equidirectional skid. When calculating wheel pressure of the skid wheel, vertical load of two
relevant sets of crane shall be determined according to the taken-value principle in item (2).
2.3.2.3 When boiler room is setting with erection crane (considering one set), it shall be
considered as setting up one set of crane in the steam turbine house, its load taken-value
is same as article 2.3.2.1.
11
2.4 Wind load shape coefficient
2.4.1 When determining wind load shape coefficient in the main building, it may not consider
defilade influence of the outdoor boilers generally.
Wind load shape coefficient in the main building may be adopted according to table
2.4.1.
2.4.2 When determining wind load shape coefficient of suspensory boiler furnace shaft in the
open air, it may not consider defilade influence of the main buildings generally.
Wind load shape coefficient of suspensory boiler furnace shaft in the open air may be
adopted according to table 2.4.2. Table 2.4.1 Wind load shape coefficient in the main building
SN Shape and shape coefficient
1
2
3
12
4
5
6
13
7
8
Table 2.4.2 Wind load shape coefficient of suspensory boiler furnace shaft in the open air
14
3 Main building
3.1 Frame (bent) structure
3.1.1 Structural arrangement shall be simple, order and reasonable, with explicit stress and it
shall take extension conditions into consideration.
Frame-bent span, spacing of columns, height of course, etc. shall consider adopting
uniform building modular system.
When it adopts fabricated structure, turbine and boiler should adopt arrangement of unit
system to reduce constructional element varieties and improve assembly level.
3.1.2 Structural style is determined after the comprehensive technical and economic
comparison for factors such as material handling, natural conditions, execution conditions,
attendance, and implementation scheduling, etc.
Frame-bent of the main building shall adopt reinforced-concrete structure, when
conditions permit, it may use composite structure, where platforms in turbine and boiler
operation layer should adopt combination beam structure. Main bearing structure of main
building with machine groups are 300 MW and more than 300 MW, it may adopt steel
structure if necessary.
Composite structure may be designed by referring to "Tentative Specifications for the
Design of Steel-Concrete Composite Structure of Thermal Power Plant.”
Sectional dimension of constructional elements of reinforced-concrete frame-bent shall
be coordinated and unified, beam column sectional dimension of main building frame-bent
should be adopted according to table 3.1.3. Table 3.1.3 Beam column sectional dimension of main building frame-bent (mm)
Constructional element Width Height
500 800 1000 1200 1400 1600
600 800 1000 1200 1400 1600 1800 2000
700 1000 1200 1400 1600 1800 2000 2200 Column
800 1000 1200 1400 1600 1800 2000 2200 2400
400 800 1000 1200 1400 1600
500 800 1000 1200 1400 1600 1800 2000
600 1000 1200 1400 1600 1800 2000 2200 2400 Main beam
700 1600 1800 2000 2200 2400 2600 2800
250 300 350 400 450 500 600 700 800
300 500 600 700 800 900 1000 1200 Junior beam
400 600 700 800 900 1000 1100 1200 1400 1600
Sectionlization of assembler reinforced-concrete frame structure shall be determined
according to construction machinery and site conditions, and it shall reduce constructional
elements and jointed type and quantity.
3.1.4 The maximal spacing of longitudinal temperature expansion joint for the
reinforced-concrete frame structure with cast in-situ structure should not exceed 75 m,
fabricated structure should not exceed 100 m. Spacing of temperature expansion joint shall
adopt integral multiple of boilers unit spacing. Structure lies in dry climate and summer torrid
and rainstorm frequency region may reduce spacing of temperature expansion joint properly
15
according to service experience.
When there are adequate argumentation, and calculating by taking effective measures or
with temperature effect, it may augment spacing of temperature expansion joint properly.
3.1.5 Modus operandi of temperature expansion joint shall adopt dual columns and dual roof
trusses, beam slab and fender structure should adopt overhanging structure. Data grade
foundation beam should adopt freely supported beam.
3.1.6 Connection of assembler longitudinal frame beam/column may adopt rigid connection
or swing connection. When adopting swing connection, it shall be set with intercolumnar
bridging or rigidity straddle.
Intercolumnar bridging or rigidity straddle should be set in the middle of temperature
expansion joint zone and along overall height of the column, and approach to one side of the
shaft line or crane beam of the column. When column section height is 1800 mm and more
than 1800 mm, it shall set a beam of support in both sides of the column.
3.1.7 Corbel top level of the bearing roof truss shall be set with longitudinal coupling-wall
beam along full length.
3.1.8 Prefabricate floor should adopt double T plate or trough plate. When slab span is larger
than 9 m, slab main rib shall adopt prestressed reinforcement.
3.1.9 Main building frame may make internal force analysis according to longitudinal and
transverse plane structure system. Transverse structure shall select some representative frame
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
3.2.12.1 Through-type steel roof truss shall dispose longitudinal bracing (figure 3.2.12-1) on
the first period of the upper chord of the roof truss. It should dispose flexible tied along full
length at the lower chord kink section and connect with lower lateral bracing (figure
3.2.12-2).
24
Figure 3.2.12-1 Longitudinal Bracing Disposal of Through-type Roof Truss
25
Figure 3.2.12-2 Disposal of Flexible Tied at Kink Section of the Through-type Roof Truss
3.2.13 Disposal of longitudinal horizontal-bracing for trapezoidal steel roof truss:
3.2.13.1 Trapezoidal steel roof truss should dispose longitudinal horizontal-bracing in the
lower chord.
3.2.13.2 Spacing of trapezoidal roof with purlin system is equal to 12m and its span is larger
than 36 m, it should not only dispose longitudinal horizontal-bracing at the lower chord, but
also set up longitudinal horizontal-bracing at the upper chord.
3.2.13.3 Disposal of longitudinal bracing for roof truss shall form closed bracing system with
the transverse horizontal shoring.
3.2.14 Disposal of vertical bracing for steel roof truss:
3.2.14.1 Trapezoidal roof truss parallel chords roof truss shall not only set up a beam of
vertical bracing at both ends of the roof truss, but also set up roof truss middle according to
the following conditions:
(1) When span of roof truss is no larger than 30m, no matter whether there are scuttle or
not, it shall add a beam of vertical bracing inside the montant plane in the middle of the roof
truss (figure 3.2.11-1 and figure 3.2.14-1).
26
Figure 3.2.14 - 1 Bracing Disposal of Roof Truss and Monitor Frame when Scuttle extends to both ends of
the Factory Building or through Temperature Expansion Joint
(a) Upper cord bracing disposal of roof truss; (b) Lower chord bracing disposal of roof truss; (c) Upper cord bracing disposal of
monitor frame
(2) When span of roof truss is larger than 30 m and less than or equal to 36 m as well as
without scuttle, it shall still add a beam of vertical bracing inside the montant plane away 1/3
of the span (figure 3.2.14-2). When span of roof truss is larger than 36 m, it shall add a beam
of vertical bracing for each increased 12 m.
(3) When span of roof truss is larger than 30m and with scuttle, it shall add a beam of
vertical bracing inside the roof truss montant plane at the bottom of the scuttle heel post
(figure 3.2.14-3).
Figure 3.2.14-2 Vertical Bracing Disposal of Roof Truss without Scuttle
27
Figure 3.2.14-2 Vertical Bracing Disposal of Roof Truss with Scuttle
3.2.15 Disposal of upper and lower chord on the steel roof truss:
3.2.15.1 Factory building without purlin shall dispose horizontal tie in the roof truss
compartment not setting with vertical bracing which is similar to node of upper chord and
lower chord of the roof truss perpendicular to the supporting plane (figure 3.2.11-1, figure
3.2.11-2 and figure 3.2.14-1).
Figure 3.2.16 Disposal of Rigid Tie Bar at the Node connecting with Lower Pressure Bar of the Column
Rigid Connection
Horizontal tie in the roof system and roof truss upper chord may be replaced by purline,
by this time, it only sets horizontal tie along full length at lower chord node of correspondent
roof truss (figure 3.2.11-1, figure 3.2.11-2 and figure 3.2.14-1).
3.2.15.2 For span of roof truss is larger than 30 m and is set with factory building without
28
purlin roof system, it shall add a beam of horizontal tie at the node of upper chord peak.
Figure 3.2.18 Rigid Tie Bar Figure added on the Lower Chord of the Roof Truss when setting with Hanging
Crane
3.2.15.3 Horizontal ties along full length setting at the major bracing node of the roof truss
end and peak node of the roof truss upper chord shall all adopt rigid tie bar (pressure bar),
others shall adopt flexible tied (drawbar). When there is bracket chord or reinforced-concrete
collar tie beam or joining beam at the major bracing node of the roof truss end, it may use this
to replace rigid tie bar.
3.2.16 For steel roof truss rigid connecting with column and without lower chord longitudinal
horizontal-bracing, and when internode bar at end of lower chord bearing pressure, it shall set
rigid tie bar along full length at internodal node of the lower chord end, and it shall connect
with lower lateral bracing (figure 3.2.16).
3.2.17 Bracing disposal of steel monitor frame shall coordinate with lateral bracing, vertical
bracing and horizontal tie of the roof truss upper chord, it shall be set within the same roof
truss compartment (figure 3.2.11-2 and figure 3.2.14-1).
29
3.2.18 When hanging crane operating along longitudinal direction of the factory building and
the crane rail not passing through lower lateral bracing of the roof truss at both ends of the
factory building and temperature expansion joint zone, it shall add rigid tie bar at the end of
the rail and it shall connect with lower lateral bracing (figure 3.2.18).
3.2.19 Disposal of top lateral bracing for the steel monitor frame:
3.2.19.1 Purlin system or without-purlin system shall both set top lateral bracing at both ends
of the monitor frame (figure 3.2.11-2 and figure 3.2.14-1).
3.2.19.2 When length of temperature expansion joint zone is larger than 75 m and less than or
equal to 100 mm, it shall also set a beam of top lateral bracing at upper chord of monitor
frame in the middle of this zone.
3.2.20 Disposal of vertical bracing for the steel monitor frame:
3.2.20.1 No matter what dimension the monitor frame span is, they shall set vertical bracing
for each in the monitor frame compartment with top lateral bracing and inside the vertical
plane of the both sides upright columns of the scuttle (figure 3.2.11-2 and figure 3.2.14-1).
3.2.20.2 When monitor frame span is larger than 12 m, it shall add a beam of vertical bracing
inside the montant plane in the middle of the monitor frame.
3.2.21 Disposal of top horizontal tie for steel monitor frame
3.2.21.1 Top horizontal tie of the monitor frame with purlin system may be replaced by
purlin.
3.2.21.2 In the without-purlin system, no matter what dimension the monitor frame span is,
they shall set flexible tied at the upper peak node and the monitor frame compartment with
top lateral bracing (figure 3.2.11-2 and figure 3.2.14-1).
3.2.21.3 When the scuttle is set with upper chord horizontal tie at both sides of the monitor
frame may be replaced by side window waler.
3.2.21.4 When scuttle is not set with sash (open style) and other longitudinal members, it shall
set flexible tied at the upper chord tip node of both sides of the monitor frame.
3.2.22 Stipulation for bracing structure is as follows:
3.2.22.1 On the roof truss, lower lateral bracing and longitudinal horizontal-bracing should
adopt cross diagonal member, bracing crossing angle should be within 30°-60°.
3.2.22.2 Section forms of the bracing member by the steel: drawbar may adopt single-angle or
double-angle steel; pressure bar should adopt form sections constituted by double angle steel.
When roof span is equal to or larger than 9m, it may adopt lattice type bracing constituted by
sections.
3.2.23 Bracing disposal of reinforced-concrete roof truss may refer to disposal of bracing
system of the steel roof truss.
3.3 Fender structure
3.3.1 Walling structure of the main building shall be in accordance with bearing structure
system.
When the bearing structure system is reinforced-concrete frame structure, walling
structure should adopt large wall panel. Wallboard type-selection shall be determined by
principles of using local materials and adjusting measures to local conditions according to
operating requirement. When it is difficult to adopt wallboard, it may also adopt masonry
30
structure.
If necessary, fender structure may adopt light material such as clad steel plate and metal
die steel plate, etc.
3.3.2 Large wall panel shall make strength and crack resistance calculation according to
construction and operational phase, and it shall checkout deflection in horizontal direction at
the operational phase.
When wallboard bearing sole weight and horizontal wind load at operational phase, it
may be calculated according to unidirectional bending member respectively.
3.3.3 When adopting light wallboard, walling skeleton beam and column section shall be
determined by calculation, calculated deflection of the wall trestle is no larger than l/400,
horizontal calculated deflection of the wall rack beam is no larger than l/200 (l is theoretical
span of the bending member). For wallboard with higher fixing requirement, calculated
deflection of the wall rack beam shall reduce properly.
3.3.4 Binding ironworks of the large wall panel shall be with adequate safety stock. The
binding types shall be simple and convenient to construction. Dimension of the buried iron
shall augment 2 mm and it shall be no less than 8 mm properly by considering influence of
the construction error and increasing its thickness comparing with calculation requirement.
Diameter of the connecting bolt shall also augment 2 mm and it shall be no less than 16
mm comparing with calculation requirement.
3.3.5 Gable skeleton at the fixed end should adopt reinforced-concrete structure. When
adopting assembler reinforced-concrete structure or larger gable span, wind beam may adopt
steel structure.
Walling structure of the gable shall conform to sidewall of the main building.
3.3.6 Gable at the fixed end should be disposed separately from the mill construction. Wind
beam of the gable shall connect with column of the main building, connection of gable
column and roof truss shall all adopt connecting types that can transfer horizontal load and
with free setting function.
3.3.7 When platform structure is set at the fixed end, disposal of gable column should
constitute frame pattern with platform structure. Upper extreme of the gable column may be
set with wind beam bearing and may also be braced at the lower or upper chord node of roof
truss.
3.3.8 When calculating wind load of the fixed end gable, wind load shape coefficient takes
μs=±1.1.
Calculated deflection of the wind beam should not be larger than l/300. When adopting
self bearing bricking-up act as fender structure, calculated-deflection of its wind beam should
not be larger than l/500 in order to prevent from bricking-up crack.
3.3.9 Stipulation for calculated length of the gable column is as follows:
Inside gable plane l0=1.0H1
Outside gable plane l0=1.25Hc
Where: H1——Distance between beams (wind beam or joining beam) inside gable
plane;
Hc——Spacing between wind beams
3.3.10 Under the action of horizontal load, internal force of the gable structure may be
calculated according to cross beam. When stiffness ratio of the wind beam and gable column
31
is
l
H
I
I
Ecolumn
EKK
column
beambeam , where H is the height of gable column, l is the wind beam
span bearing on the factory building column, when l is larger than 10, it may make simplified
calculation according to the following principles:
3.3.10.1 Wind beam may be calculated according to freely supported beam with both ends
bearing to main building column; it neglects elastic bearing action of the gable column.
3.3.10.2 Gable column may be calculated according to coupling-wall beam bearing to wind
beam and it shall consider additional bending moment and shearing force generated by
deflection of wind beam in the bearing point to gable column.
3.3.11 Gable at extension end shall consider the handiness of installation and removal.
Skeleton should adopt hybrid combination steel structure or assembler reinforced-concrete
column and steel wind beam. All the connections should adopt screw bolt.
Walling structure shall be light weight, firmness, duration, and simple and convenient
removal according to thermal retardation requirement.
3.3.12 Gable at the extension end may choose direct suspension wallboard form for triangular
truss. Triangular truss is reducible to plane system, and calculated according to general steel
truss, calculated deflection in vertical direction is no larger than l/500.
Upper and lower chord of the truss should adopt close type section, web member may adopt
single-limb angle steel.
Connection of triangular truss and factory building column as well as connection with
wallboard should adopt screw bolt.
3.3.13 When calculating gable wind load of extension end, wind load shape coefficient takes
μs=±0.8.
3.3.14 Extension end gable should adopt single column and simple footing to reduce collision
of dismantle workload and channel when extension.
3.4 Coal scuttle and crane beam
3.4.1 Coal scuttle shall adopt reinforced-concrete structure or steel structure; coal scuttle
shape shall be simple and adopt form easy to break down and with rational resultant.
Coal scuttle of high-capacity machine unit should adopt steel structure. When working
temperature of powder coal scuttle exceeds 80℃, it shall adopt comminuted steel shot scuttle.
3.4.2 Design conditions coal bunker is provided by technology and it shall meet the following
requirements:
3.4.2.1 Coal bunker should adopt silo structure and connect hyperbola or cone exit section at
its bottom, its inside wall shall be lubricious and antifriction, hyperbola exit section shall not
contract suddenly, cut-angle of the cone exit section and horizontal plane is no less than 60°.
3.4.2.2 Included angle of the adjacent two wall intersections and horizontal plane of coal
bunker for the non-silo structure is no less than 55°, and cut-angle of its wall surface and
horizontal plane shall not be less than 60°. For the lignite and soft coal with high-viscosity or
flammability, included angle of its adjacent wall intersections and horizontal plane is no less
than 65°, and cut-angle of its wall surface and horizontal plane shall not be less than 70°.
Inner side of the adjacent wall cut-angles shall be made into circular-arc; radius of the circular
32
arc should not be less than 200 mm.
3.4.3 Design for powdered coal bunker shall meet the following requirements:
3.4.3.1 Powdered coal bunker shall be closed, its internal surface shall level off, lubricious
and antifriction, and it shall not accumulate powder and be without steps of detenting coal
dust.
3.4.3.2 Powdered coal bunker shall prevent from wetting; it shall adopt thermal retardation
measures for coal bunker ectotheca of the comminuted steel shot. In the cold area, near to the
external wall of the factory building or powdered coal bunker exerted shall be taken with
thermal retardation measures.
3.4.3.3 Included angle of the two adjacent wall intersection lines and horizontal plane of the
powdered coal bunker shall not be less than 60°, and the cut-angle of wall surface and
horizontal plane shall not be less than 65°, inner side of the adjacent wall cut-angle shall be
made into circular-arc, circular arc radius should not be less than 200 mm.
3.4.4 Physical characteristic factor of coal and coal dust shall consider the feeding material
quality and operating condition properly. Its data shall be provided by technology, if there are
no data, it may select by referring to the data list in table 3.4.4. Table 3.4.4 Physical Characteristic Factor of Coal and Coal Dust
Name of material Gravimetric density (kN/m3) Angle of internal friction φ (°) Friction factor of material to steel plate
Anthracite 8.0—12.0 25—40 0.30
Lignite 7.0—10.0 23—38 0.30
Soft coal 8.0—11.5 25—40 0.30
Coal dust 8.0—9.0 25—30 0.40
3.4.5 When calculating coal bunker load, it shall be considered as full load, load on
crossbeam shall be distributed according to gravity centre of the coal bunker. Powdered coal
bunker and its top floor structure shall be able to bear possible blasting power generated in
the bunker. Dimension of the blasting power shall be designed as 10 kN/m2 (gage pressure).
Floor slab should adopt cast-in-situ plate or set reinforced cast-in-situ layer on precast slab.
Steel bar in cast-in-situ layer shall credibly connect with protruding steel bar on the bearing
structure. Connection of pipeline (or manhole door) and floor shall be able to resist explosion
pressure.
Shallow coal bunker High wall shallow coal bunker
Figure 3.4.6 Shape of Coal Bunker
3.4.6 Internal force calculation of the reinforced-concrete coal bunker shall consider the
33
in-tension inside the wainscot plane and bent outside the wainscot plane, it shall also consider
bent inside the wainscot plane for the suspended type coal bunker.
Calculation for bent inside the headwall plane may adopt method of approximation:
shallow coal bunker may make calculation according to theory of folded plate structure
without bending moment; vertical wall of high-wall shallow coal bunker may be calculated
according to deep beam, the skew wall's action is negligible (figure 3.4.6).
3.4.7 Calculation of assembler reinforced-concrete coal bunker is related to structural shape,
block division and node structure, etc. of coal bunker, there are three types in common use:
3.4.7.1 Vertical wall of coal bunker of the bearing lateral blocking (such as cage drawer type)
may be calculated according to close frame, horizontal joint is connected according to
structure.
3.4.7.2 For coal bunker of bearing vertical blocking, vertical wall may be calculated
according to simply supported plate, perpends among the plates are connected according to
structure.
3.4.7.3 Internal force analysis of suspended type coal bunker is same as cast-system coal
bunker and it shall be designed by referring to the joint of general assembler
reinforced-concrete structure.
3.4.8 Headwall thickness of flatbed coal bunker of the reinforced-concrete takes 1/20- 1/30 of
its minimal side length when skew wall of the coal bunker is triangle; it takes 1/20- 1/30 of
the smaller value of its height or average width when skew wall of the coal bunker is
trapezoid. The minimum thickness of cast-in-situ flatbed headwall is no less than 150 mm,
when adopting fabricated structure, it shall be no less than 120 mm. thickness of the steel bar
inhibitory coating in the inner side of the headwall shall not be less than 20 mm, when it
doesn't add inner lining, thickness of the steel bar inhibitory coating shall be thicken to 40
mm.
3.4.9 The maximal crack width allowable value of the reinforced-concrete coal bunker
headwall is 0.2 mm.
3.4.10 Bunker month beam at the coal bunker exit or small steel bunker of built-in fitting
hanging shall consider the influence of abrasion and corrosion, their calculated load shall
consider weight of top coal column and suspensory material.
3.4.11 Headwall thickness of coal bunker for the steel structure shall be thickening for 2 mm
comparing with calculated value, and it shall be no less than 10 mm.
3.4.12 Steel coal bunker should adopt bearing silo, it may adopt bearing with eight points.
Deflection of crossbeam of the bearing coal bunker shall not exceed 1/600 of the span.
Deflection difference between any two bearing points shall not exceed 5 mm.
3.4.13 Bearing coal bunker shall be broken away from the belt layer structure, and it shall
adopt measures to prevent coal dust dissipation.
3.4.14 Connection of steel coal bunker and concrete bearing structure shall be left with certain
fixing clearance and it shall be able to adapt to certain construction errors.
3.4.15 Steel silo shall not only meet strength requirement, but also checkout integer
stabilization of the cylinder if necessary.
3.4.16 Rectangular steel coal bunker may adopt flat steel and angle steel, etc. to act as a
ribbed stiffener. Its carrying capacity may be determined according to compound section of
ribbed stiffener and wainscot, by this time, effective width of compression flange is: when
34
plate is No. 3 steel, it takes 30t, when plate is 16 manganese steel, it takes 25t (t is calculated
thickness of the wainscot).
3.4.17 When adopting wainscot of steel coal bunker, wainscot deflection shall not be larger
than 1/150 of the span of slab, deflection of ribbed stiffener shall not be larger than 1/250 of
its span.
3.4.18 When there are screw bolt or stress fillet weld in the inner side of the steel coal bunker,
it shall add some frame covering on it. Frame cover thickness may take 4-6 mm.
3.4.19 Ectotheca of steel coal bunker and inside wall within 1.5 m away from the coal bunker
tip shall be painted with antifouling paint, other parts shall not be painted.
3.4.20 Structure type-selection of crane beam shall be adopted according to table 3.4.20. Table 3.4.20 Structure Type-selection of Crane Beam
Span of crane
beam (m)
Payload capacity of crane
nameplate (t) Structure type-selection
l<9 Q≤75; Q>75 Solid web beam of reinforced-concrete①; it should adopt solid web beam of
prestressed reinforced-concrete②
9≤l≤12 Q≤75; Q<75 It should adopt solid web beam of prestressed reinforced-concrete②; it shall
adopt solid web beam of prestressed reinforced-concrete③
① Condition permitting, it may adopt solid web beam of prestressed reinforced-concrete;
② When construction and material condition is limited, it may adopt solid web beam of reinforced-concrete;
③ When construction and material condition is limited, it may adopt steel crane beam
3.4.21 Crane beam shall combine with engineering condition to checkout load on crane test
and be during the equipment installation (dynamo stator, etc.) process, by this time, its safety
class may reduce one level comparing to operational phase.
3.4.22 When calculating crane beam, it shall consider orbit center and eccentricity of vertical
center line of the beam section, its numerical value is no less than 20 mm.
3.4.23 Crane beam of constant section reinforced-concrete may make carrying-capacity and
crack resistance calculation of midspan in the operational phase according to unidirectional
bending member.
3.4.24 Lateral braking force of the crane may be supposed to act on sectional gravity centre of
the crane beam top flange, and they are all bearing by flange, taking no account of co-action
of web plate and lower flange.
3.4.25 Crane beam should adopt overhanging structure at the expansion joint.
3.4.26 Main reinforcement inside the beam shall not adopt colligating joint, and it should not
adopt welding joint. It shall not weld any appendix to the steel bar (excluding end anchorage).
When the steel bar length is inadequate, it shall be in compliance with relevant clauses in
"Design Specifications for Concrete Structure.”
3.4.27 In order to prevent horizontal fractures generated at the end of the beam when making
prestress construction, it shall set vertical reinforcement along depth of beam and be matched
with lateral stirrup to form puncheon. Diameter of the stirrup is no less than 6 mm, the
spacing is no larger than 100 mm, configuration scope is h/4 (h is the height of beam end).
Diameter of vertical reinforcement is no less than 12 mm; its lower end is welded with
anchorage plate, its upper end diving into top flange of the beam.
3.4.28 When web plate of the crane beam is too wide, connecting bolt of crane beam and
crane rail should adopt imbed method with leaving holes, vug may be cast with sulphur
mortar after screw bolt finding its position.
3.4.29 Steel crane beam shall adopt simple support connection in perpendicular and horizontal
35
directions. Connection with column and platform shall adopt screw bolt.
3.4.30 Steel crane beam should adopt I-shaped cross-section with equal altitude and constant
section. Connection of flange and web plate may adopt continuant corner fillet, weld of the
top flange shall not only bear horizontal shear force between flange and web plate, but also
bear vertical shear force generated by crane wheel pressure.
When throat thickness is larger than 16 mm, it shall adopt double-bevel butt weld. Weld
quality shall not be less than the second grade weld standard.
3.4.31 Bearing ribbed stiffener of steel crane beam at expansion joint overhanging section
may adopt flatbed bearing ribbed stiffener, other parts should adopt lug bearing ribbed
stiffener. Both ends of the flatbed bearing ribbed stiffener shall be plane and be close to the
lower flange. Ribbed stiffener lower end of the lug bearing shall be plane. Steel crane beam
end shall be set with dunnage, the dunnage width should not be larger than 100 mm, and its
thickness is determined according to calculation and is no less than 30 mm.
3.4.32 Connection of top flange of the steel crane beam and column shall prevent large stress
caused by partial built-in of crane beam from structure.
3.5 Framework of suspensory boiler
3.5.1 This section is applicable to reinforced-concrete boiler cradle and composite structure
boiler cradle of suspensory boilers with capacity is 670t/h and below.
3.5.2 When designing boiler framework, it shall determine rational design proposal for boiler
cradle according to boiler manufacturer information provided by technology and under close
cooperation of the boiler manufacturer, and it shall require the manufactory satisfying the
following conditions:
3.5.2.1 Large plate beam layer shall be set with sealing lateral bracing by the manufactory to
form rigid diaphragm.
3.5.2.2 Boiler cradle not bear the boiler blasting power
3.5.2.3 When it requires setting shaking point, it should be set on the operation with bigger
rigidity or elevation of the overhauling platform.
3.5.3 Bearing construction mode of large plate beam and framework column shall be
determined by together studying with boiler works. Components such as bearing dunnage, etc.
shall be supplied by manufacturer. Large plate beam and column coupling should adopt swing
joint.
3.5.4 Framework of suspensory boiler should adopt disposal of independent type.
3.5.5 Boiler framework column may adopt single column of rectangular section, battened
column or frame column according to its strength and stability condition. Transverse direction
of boiler framework should add beam (or truss) in the intercolumniation to form multistory
frame structure. Longitudinal direction of boiler framework shall be set with longeron along
column height to form multistory frame structure. When adopting battened column, each
layer of longeron shall disposal in pairs.
3.5.6 When adopting frame boiler cradle, it shall select beam column section reasonably to
reduce additional stress influence owing to axial deformation of columns.
3.5.7 Boiler framework is integer space structure. In order to simplified calculation, it may
make stress analysis according to longitudinal and transverse plane structural system. Design
36
schedules of boiler cradle in common use see appendix B.
3.5.8 For boiler framework with open air arrangement, itemize factor of wind load shall take
1.4 in basic combination of the loads, other itemize factor of variable load shall take 1.3.
Combination factor of wind load and other variable load shall take 0.85. Basic wind velocity
pressure shall multiply by factor 1.1. It shall take no account of wind shakiness and 45° wind
load when calculating.
3.5.9 Wind load on boiler body and boiler cradle should be calculated respectively owing to
their different shapes. Wind loads on boiler body are all act on boiler cradle top through
suspensory bar. For the boiler cradle setting with shakiness-resistance device shall be checked
with its local strength of corresponding load-bearing member of the boiler cradle.
3.5.10 When the large plate beam layer in the roof is rigid diaphragm, horizontal load on
framework top shall be distributed according to rigidity proportion of each framework. When
the allocation proportion of middle framework is insufficient to 10%, it should be calculated
as 10%.
3.5.11 Boiler framework shall be with adequate rigidity. Under the action of wind load,
horizontal displacement value of the framework column top shall not be larger than H/750
(H——height from fundamental top surface to column top).
3.5.12 When calculating boiler cradle: it must consider eccentricity influence of construction
error to boiler cradle, that is, it may add an additional bending moment on column top
(calculating respectively for vertical and horizontal directions). Eccentricity may adopt 1‰ of
the column total height and it shall be no less than 50 mm.
3.5.13 Calculated length of frame column of the boiler framework may be determined
according to appendix C.
3.6 Elevator shaft structure of the boilers
3.6.1 Requiring fundamental dimensions when designing elevator shaft structure, floor
elevation of elevator staying and melt pit depth shall be determined according to technology
profession and information submitted by elevator manufacturer.
3.6.2 Elevator shaft structure should adopt outer attached disposal, it may also adopt
independent type and inner attached disposal forms otherwise.
3.6.3 Elevator shaft structure may adopt reinforced-concrete structure when disposing
according to independent type. And it should adopt steel structure when it is according to
attached form. Outer attached steel structure shall be vertical direction and it shall make
boiler cradle platform act as horizontal pivot at some distance. The pivot shall be made into
immobile pivot on the structure.
3.6.4 Wind load on elevator shaft structure shall act as primary load. For the elevator shaft
structure disposed with independent type shall consider wind shake factor when calculating
wind load.
3.6.5 Controlling value of horizontal displacement for the column top of the elevator shaft
structure should not be larger than H/500 (H is height from fundamental top surface to
column top).
3.6.6 Elevator shaft should adopt light material act as fender structure.
37
3.7 Frame-bent steel structure
3.7.1 Structural steel design for main building shall comply with current design specifications
of the nation; it shall also meet the requirement of this standard.
3.7.2 Steel structure of main building shall make internal force calculation according to elastic
designation without reference to adopting system with bracing structure or without.
3.7.3 Disposal of floor beam system of oxygen removal bunker bay in the main building shall
make comprehensive consideration for the integer rigidity and stress reasonableness for the
factory building, it may adopt mode of making longeron act as the main beam main beam
(that is, junior beam adopt disposal of transverse direction), or may adopt mode of making
transbeam act as main beam (that is, junior beam adopt disposal of longitudinal direction).
Beams intercolumnar in longitudinal direction should be set in the same shaft line.
3.7.4 Bracing disposal shall consider stabilization of the structural system, integer rigidity,
horizontal load transference, calculated length of the constructional element, etc.
Bracing forms and its disposal shall conform to professional pipeline and cable trend of
relevant technology.
3.7.5 It shall set end vertical bracing in the first intercolumniation within both ends and
temperature joint zone of the factory building. This bracing should be set within the scope of
corbel plane of crane beam to column top and it shall conform to lower lateral bracing of roof
truss. Parts below the crane beam shall adopt double-limb bracing.
3.7.6 Shaft lines perpendicular to support bar should intersect at the crossing point of shaft
line of the beam column. When it is difficult to be satisfied, they may intersect at the edge of
the beam and column flange. By this time, calculation for bearing capacity of beam and
column shall consider eccentricity moment caused by eccentric connection.
3.7.7 Member disposal for bracing system shall be with explicit conducting force, and short
and nimble path. It shall consider the following factors when calculating:
3.7.7.1 When calculating internal force of perpendicular support bar, it may take no account
of additional stress caused by axial deformation of the members.
3.7.7.2 If the bracing is eccentricity connection, its eccentricity end shall be calculated
according to eccentric link without reference to type of the bracing.
3.7.7.3 When the vertical bracing in endostyle compartment of expansion joint interval of the
same columniation is bigger than the first crosspiece, the horizontal force bear may be
determined according to swing rigidity distribution of each crosspiece of the vertical bracing.
When each layer of vertical bracing is not in the same intercolumniation and difference of the
column sectional area is no larger than 30%, it may make internal force analysis as vertical
bracing in the same intercolumniation.
3.7.7.4 Each layer of vertical bracing is not in the same intercolumniation, if it requires
calculating horizontal displacement, it may be determined by delamination calculation and
then superimposes the result.
3.7.7.5 When setting with double-limbs bracing, connecting tie bar used for reducing
calculated length of compression member of the bracing shall be with axial force is 2% of the
bracing axial force.
3.7.7.6 The minimal connection of bracing with column and beam should be 50% of the
calculated resisting power of the pressure bar.
38
3.7.8 Bearing capacity of channeled steel plate for reinforced-concrete floor shall not only be
calculated according to "Engineering and Construction Regulation for Metallic Contour
Plate,” but also meets the following requirements:
3.7.8.1 Construction live load of the contour plate takes 2 kN/m2.
3.7.8.2 Connection of contour plate and steel beam should adopt plug welding. Diameter and
spacing of plug welding shall be determined according to calculation and structure.
3.7.8.3 When steel beam is set with shear resistant pieces, contour plate and steel beam flange
compartment may be set with structural weld, contour plates may be not welded.
3.7.8.4 Deflection of contour plate in construction phase shall not be larger than 1/180 of the
span.
39
4 Groundwork and foundation
4.1 Fundamental rules
4.1.1 According to the engineering geology investigation, the groundwork foundation design
shall adopt the safe, economic and rational subgrade foundation type by combining the
operating requirements of all kinds of structures in thermal power plant; fully learn the local
architecture experience, and comprehensively considering such factors as the structure type,
material conditions and execution conditions.
4.1.2 According to the seriousness of the destroying consequence on structures caused by the
destruction of foundation, the structures in thermal power plant are classified into three safe
classes (Table 4.1.2). Table 4.1.2 Safe Class of the Foundation of Structure
Safe
class
Destruction
consequence Structure name
Class
I Very severe
Main workshop (including foundation of steam turbine generator and the foundation of the boiler
framework), main control building or network control building, communication building, indoor
220kV power distribution unit building, chimney higher than 100m, dry coal shed with span larger
than 30m, and other plant buildings
Class
II Severe
Other manufacturing buildings, auxiliary and appurtenant structures except those of class I and III
Class
III Not severe
Machine and furnace overhaul room, material storage, engine shed, motor depot, material
warehouse, coal transporter warehouse, guardhouse and gate chamber, enclosing wall of plant site,
bicycle shed, and temporary construction
4.1.3 The groundwork foundation shall be designed according to the engineering geology
investigation information of the corresponding design stage. As for complicated geologic
conditions (such as groundwork in mountainous area and special foundation soil), the
necessary site geological examination shall be carried out at construction stage.
4.1.4 The groundwork design of main workshop should adopt the groundwork of the same
type. Different structural units may also adopt different groundwork type and different pile
supporting course according to the engineering geologic conditions by considering the
settlement characteristics of each unit of the main workshop.
4.1.5 The main workshop foundation should adopt same buried depth or be buried in
sublevels, or may also adopt the partial deeply burying mode (such as the foundation arranged
with water circulation pipe, breach, and sump hole).
4.1.6 The structures of class I and the structure of class II that requires the settlement
observation shall have the settlement observation at the construction period and operating
process, and the field data shall be taken as one of the reference for the quality inspection on
the foundation work of groundwork. The observation procedure and requirement may be
referred to the relevant provisions specified in "Code for Design of Building Foundation"
Annex A and "The Code of Erection and Acceptance for Electric Power
40
Construction-Construction Engineering Section".
4.2 Foundation calculation
4.2.1 According to the safe class of structure foundation, the foundation calculation shall be
carried out according to the following requirements:
4.2.1.1 The foundations of all the structures shall have the calculation on ground bearing
capacity.
4.2.1.2 The structures of class I and II not only shall be calculated according to ground
bearing capacity, but also shall have the calculation on foundation deformation, but when one
of the following conditions is met, the deformation computation may be omitted.
(1) When the main workshop foundation is uniform and the standard value of ground
bearing capacity comply with Table 4.2.1. Table 4.2.1 Ground Bearing Capacity when Main Workshop not Having Foundation Deformation
Calculation
Unit capacity
(MW)
Standard value for ground bearing capacity of the main
stressing layer of natural foundation
fk(kPa)
12~25 ≥180
50~100 ≥220
200~300 ≥270
600 >300
Notes: 1. The main stressing layer of foundation refers to the scope of 3b (b is the width at foundation base) in depth and
thickness not less than 5m under the foundation base;
2. The collapsible loess foundation is excluded.
(2) As for the structure of class II, when the geologic condition and structure type comply
with the scope specified in Table 2.0.2 of "Code for Design of Building Foundation".
(3) When the regional mature experience or similar engineering experience may be
available for referring.
4.2.1.3 The structure constructed on slope shall also be recalculated for the foundation
stability. The building structure (such as retaining wall) being frequently under function of
horizontal load shall be recalculated for its foundation stability if necessary.
4.2.2 When calculating the foundation deformation, the load transferred to the foundation
base shall be assembled according to long-term effect, the wind loads and direct-transmitted
shock effect shall not be considered.
The crane load of main workshop shall be considered with the load generated by the
deadweight of crane when calculating the foundation deformation.
4.2.3 The final settling volume of natural foundation and pile foundation should be calculated
according to the "Code for Design of Building Foundation" or the relevant provisions
specified in regional codes.
When calculating the final settling volume of the pile foundation of weak ground, the
pile foundation grind slab, pile group and soil among piles may be taken as solid deep
foundation, and the pressure expansion angle along the pile body shall not be considered. The
thickness of compact layer shall be accounted from the gross section of pile tip to the 20%
41
section where the supplementary pressure is equal to the deadweight pressure of soil. The
calculation of supplementary pressure shall take the influence of neighboring fundaments into
consideration; the compression modulus Es of foundation soil under the action of actual stress
shall be adopted.
When calculating the foundation deformation, it may take the foundation rigidity into
consideration.
4.2.4 The permissible deformation value of the main workshop foundation shall comply with
those specified in Table 4.2.4, and the permissible deformation value of the other structures of
class I and II may refer to the "Code for Design of Building Foundation" or the relevant
provisions specified in regional codes. Table 4.2.4 Permissible Deformation Value of Main Workshop Foundation
Permissible differential settlement or
inclination Tolerable settlement, mm.
Main workshop structure Longitudinal
direction
Transverse
direction
Natural
foundation
Pile
foundation
Outside column of turbine room 0.003l — 150~200 100~150
Outside column and framework of turbine
room — 0.003l — —
Main workshop framework 0.003l 0.002l 200 150
Steam turbine generator foundation 0.0015l 150~200 100~150
Boiler foundation 0.002l 150~200 150
Foundation and framework of steam turbine
generator 0.005l —
—
Foundation and framework of boiler 0.005l — —
Notes: 1. l in the table refers to the centre distance of neighboring pillar supports or the side length of turbine foundation;
2. The pile foundation in the table refers to the foundations of precast concrete pile, pre-stressed centrifuge tubular
pile, bored concrete pile or steel-pipe pile;
3. The supporting course at pile tip shall be the intermediate and low compressible soil layer.
4.3 Weak foundation
4.3.1 The design of weak foundation not only shall comply with those specified in 4.2.1, but
also shall adopt measures to reduce the foundation deformation and the adaptable foundation
deformation of structures.
4.3.2 When the bearing capacity, deformation or stableness of weak foundation does not
comply with the design requirement, the foundation treatment should adopt the mature
method in power plant design such as the shallow layer reinforcement or the pile foundation.
The treatment method and the indices such as ground bearing capacity and compression
modulus after treatment shall pass the test and be determined by combining with the practical
experiences.
4.3.3 The following measures may be adopted in order to make the structure be adaptable to
the deformation and differential settlement of weak foundation:
4.3.3.1 The settlement joints may be set at the following positions:
(1) The joint of main workshop and neighboring structure;
42
(2) The joints among the outside column of main workshop, framework, turbine
foundation, heater platform, turbine overhauling platform, boiler cradle, boiler platform, and
gable wall.
(3) The joint of main control building and power distribution unit building;
(4) The joint of chimney and flue (generally, the settlement joint is located at the outer
margin of foundation mat);
(5) The joint if coalbreaker chamber, transfer site as well as the coal storage tank and
coal delivery trestle.
When the settlement joint is disconnected from the top to foundation with adequate
width
When setting the settlement joint is limited, the swing joint or freely supporting mode
may be adopted, but the supporting length shall be appropriately enlarged.
4.3.3.2 The monolayer structure may adopt such statically determinate structures as
trestlework and three-hinged arch rigid frame.
4.3.3.3 The settling volume of structures shall be predicted, and the corrective measures shall
be left such as increasing the clearance between the crane and structure.
4.3.3.4 As for the structure with large predicted settling volume, the design elevation of
terrace and related positions in the structure shall be appropriately heightened.
4.3.3.5 Measures shall be adopted technologically, such as increasing the clearance between
the pipeline and structure by considering the flexonics of pipelines.
4.3.4 The coal yard structure shall take the foundation differential settlement caused by the
large-area surcharge load as well as the influence on superstructure; the following measures
may be adopted:
4.3.4.1 The dry coal shed should adopt the structural style that is adaptable to foundation
subsidence.
4.3.4.2 When the dry coal shed and coal bridge adopt natural foundation, the reinforced
concrete socle should be appropriately strengthened to bear the appended bending moment
resulted from the possible rotation of foundation.
4.3.4.3 The gantry crane and stacker-reclaimer foundation on the natural foundation may be
designed into the sectional strip-shaped stiffening bar, and the corrective measures of pathway
in transverse direction and vertical direction shall be considered. The combined bottom plate
should be adopted when there is coal bulkhead.
4.4 Foundation in mountain area
4.4.1 The design of foundation in mountain area (including the highland) shall determine
rational foundation treatment project according to the torography, geologic condition, general
arrangement, plant superstructure and construction method by considering such factors as
karst (earth cave) side slope, landslide, debris flow, shattered fault zone, collapse (including
crag and creeping rubbles) as well as the excavation, filling, surcharge loading and unloading
in the process of construction.
4.4.2 In the construction in mountain area, proper measures shall be adopted to prevent the
leakage of surface water and industrial water from resulting in adverse effect on building
foundation and such adverse geologic evidence as the landsliding and erosion at construction
43
site.
4.4.3 The key structures such as main workshop, major equipment foundation and chimney
shall be set on better foundations and shall be designed according to the following provisions:
4.4.3.1 The mode of building foundation shall be reasonably selected by combining the
underlying bedrock conditions. One foundation shall not be set on the soft and hard
foundations at same time, the foundation with the surface slope of the underlying bedrock of
groundwork in the same structural unit larger than 10% shall be recalculation on foundation
deformation according to Item 4.2.1 of this code. And it shall be treated combining with the
physical circumstances of project when the deformation value exceeds those specified in
Table 4.2.4.
4.4.3.2 As for the karst foundation, the karst area and the unstable area shall be avoided.
4.4.3.3 They shall not be placed at areas where may slide or suffer from the risk of landslide,
collapse, and debris flow.
4.4.3.4 The compacted filled-in foundation should not be adopted.
4.4.4 In the construction in mountain area, the non-solidified foundation at such areas as
covered gutter, covered pond and gulch shall not be used as natural foundation.
4.4.5 With the precondition that the hillside is wholly stable, the slope design shall comply
with the following requirements:
4.4.5.1 The allowable value for the slope of side slope shall be determined according to the
local experience and referring to the stabilized slope value of similar soil (rock) body. The
side slope value shall be proposed by the geological exploration department. The
determination of design side slope value shall also consider such factors as the influence of
the position of side slope on the structure safety.
4.4.5.2 When the geologic condition is good and the soil (rock) is uniform, the allowable
value for the high wall slope of common sites and roads shall comply with the relevant
provisions specified in the "Code for Design of Building Foundation". The side slope of
neighboring key structures may be adopted by referring to the lower limit value of the
allowable side slope value in corresponding provisions.
4.4.5.3 The slope allowable value of the rock high slope may be determined by referring to
Table 4.4.5. Table 4.4.5 Allowable Slope Value of Rock Side Slope
Allowable side slope value Depth-width ratio Rock types Weathering degree
Slope height at 15~30m Slope height at 30~40m
Slightly weathered 1:0.30~1:0.50 1:0.45~1:0.75
Moderately weathered 1:0.50~1:0.75 1:0.75~1:1.00 Hard rock
Highly-weathered 1:0.75~1:1.00 1:1.00~1:1.50
Slightly weathered 1:0.75~1:1.00 -
Moderately weathered 1:1.00~1:1.50 - Soft rock
Highly-weathered - -
Notes: 1. The side slope with height of or bellow 15m shall refer to the national standard "Code for Design of Building
Foundation";
2. When using this table, the conditions such as territorial hydrology and meteorology shall be considered, and the
table shall be adjusted combining with the physical circumstances;
3. When this table is used for the side slope of the buildings that are near to the main body, the side slope value shall
44
be determined carefully and shall not be larger the lower limit value of the allowable side slope listed in the table;
4. This table is inapplicable to the side slope where the groundwater evolves or has weak structural plane and the
main joint plane has slipping along the slope aspect.
4.4.5.4 When the side slope height exceeds 8m, it should be designed into setback type for
improving its stability, one platform of 1~2m in width shall be set in the middle, and
corresponding waterproofing and drainage measures shall also be adopted.
4.4.5.5 The ramp of side slope shall be adopted with corresponding protective covering
measures according to the local hydrology and meteorology conditions, side slope soil (rock)
conditions to protect the ramp from being scoured or weathered.
4.5 Collapsible loess foundation
4.5.1 As for the structure constructed on the collapsible loess foundation, the foundation
treatment shall be carried out according to the relevant provisions specified in the "Code for
Building Construction in Collapsible Loess Regions", and corresponding design measures
shall also be adopted.
4.5.2 The structures in power plant are classified into four types according to the possibility
degree the foundation is wet by water and the consequence of settlement by soaking as well
as the strictness degree of the restriction of operation on differential settlement, see Table
4.5.2.
4.5.3 As for the structures of class A that are constructed on the self weight collapse loess site,
measures for eliminating the whole collapsibility of the under he groundwork shall be adopted.
When the collapsible soil layer under the foundation base too thick (generally is not less than
10m) to eliminate the whole collapsibility, it may be treated by adopting comprehensive
measures such as adopting rigid waterproofing measures and the structural measure that is
adaptable to foundation deformation simultaneously when eliminating the collapse settlement
of foundation. Table 4.5.2 Classification Chart of Structures
Types Structure name
A Main workshop and chimney
B Other manufacturing buildings, auxiliary and appurtenant structures except those of class A, C and D
C
Fuel pump room, fuel store, air compressor room, hydrogen production station, circulating water treatment room,
chloridization station, maintenance depot, machine and furnace overhaul room, material storage, engine shed, coal
transporter warehouse, motor depot, and fire station
D Material storage shed, guardhouse and gate chamber, enclosing wall of plant site, bicycle shed, and temporary
construction
Notes: 1. The water basins and water tanks in or near to the structures shall be classified according to the types of the
neighboring structure;
2. It may be of class A when the height of building construction is larger than 40m.
4.5.4 As for structures of class B that are on the self weight collapse loess site with large
feasibility of being wet by water (such as the chemical water treatment room), not only the
treatment measures for eliminating part of the collapse settlement of foundation shall be
adopted, but also the strict waterproofing measures shall be adopted.
4.5.5 The ground foundation design of the structure in the plant site, the adverse effect of the
45
partial settlement by soaking caused by the water leakage of hydraulic structure or pipeline
after the power plant is put into production shall be taken into consideration.
4.5.6 As for the treatment on deep collapsible loess foundation, such schemes as high-level
heavy-tamping, compaction method or hole-digging extending bottom pile shall be adopted in
accordance with local conditions. When adopting the pile foundation scheme, the influence of
negative skin friction force resulted from the settlement of soil layer by soaking shall be
counted in.
4.5.7 When treating the foundation with heavy-tamping method, the treatment scope shall be
larger than the scope of building foundation, the width that may be enlarged by 1/3~1/2 of the
planning reinforcement depth from the outer margin of groundwork, and shall not be less than
one row of ramming points. As for the conditions in Item 4.5.3, when the settlement thickness
by soaking is not wholly eliminated, the heavy-tamping width shall also be appropriately
enlarged.
When the expansion project adopts heavy-tamping method, proper measures shall be
adopted to prevent the adverse effect on the normal operation of existed structures and power
plant.
4.6 Foundation
4.6.1 The type of the column fundament in plant shall be dependent on the ground bearing
capacity or the bearing capacity of individual pile. The individual foundation may be adopted
when the geologic condition is good or the bearing capacity of individual pile is large. When
the ground bearing capacity or the bearing capacity of individual pile is small, the
strip-shaped, raft-shaped and coffer foundations may be separately adopted in sequence with
condition that meeting the foundation deformation.
4.6.2 The calculation method of strip foundation include elastic foundation method, inverse
floor slab method and shearing force balance method, which may be designed according to
former experience and be adopted with corresponding structure measures.
The ordinary constructions of the strip foundation of plant:
4.6.2.1 The height of the main girder in the strip foundation of plant should be 1/4~1/5 of the
spacing of columns. The height of the main girder in the strip foundation of other structures
should be 1/4.5~1/6 of the spacing of columns.
4.6.2.2 As for the longitudinal effective bar of strip foundation beam, the critical steel ratio at
its top and bottom shall all be 0.15%, and the more than 1/3 steel reinforcements among the
longitudinal main reinforcements are placed with uniform length.
4.6.3 The cross strip foundation is calculated according to the strip foundation at two
directions, and the column load is distributed with method that the deflections at the
directions are equal.
When the arrangement of cross strip foundation gives priority to one direction, the
calculation may also be simplified by the strip foundation at this direction, and the other
direction shall meet the requirement on the constructional critical steel ratio.
4.6.4 The calculation for the internal force of raft-plate foundation (including two types: with
or without beam) may adopt floor inverse method and shearing force balance method. When
the rigidity of raft plate is small, the elastic foundation method should be adopted.
46
The reinforcement of raft plate not only shall comply with the calculation requirement,
but also shall meet that the steel reinforcements with 0.15% reinforcement ratio at pedestal
along the longitudinal and horizontal directions are connected and all the steel reinforcements
at midspan are linked up.
The thickness of raft plate shall be determined according to the requirement on
anti-die-cutting and anti- shearing.
4.6.5 When the column grid of the superstructure is thick and the rigidity is large, the coffer
foundation may be calculated according to local bending (but the integral flection when the
superstructure does not form large rigidity in construction shall also be considered). The
integral bending shall be calculated when the forementioned conditions can not be met.
4.6.6 When adopting pile foundation, good supporting course such as clay soil, sand soil, soil
aggregate or rock with low compressibility shall be selected.
The selection for the pile type shall be determined according to the engineering geology,
execution conditions and site environment through comparative study.
When adopting driven pile, the design elevation of pile and stamping penetration shall be
analyzed by combining with the physical circumstances of project; the friction pile gives
priority to the control of design elevation. The penetration when driving the trial pile shall be
checked, and the point bearing pile gives priority to the control of penetration.
4.6.7 In new construction, the bearing capacity of individual pile at different geologic
conditions shall be determined according to the onsite static load test. The test pile scheme
must be selected combining with the geologic conditions and operating requirements. And the
test shall be carried out before the pile-making and pile-sinking (should be carried out before
the primary setting if the condition permits).
As for the expansion project, if the geologic conditions are different or the pile types and
pile length are different, the pile may also be tested.
The quantity of test piles shall be 1‰~5‰ of the total amount of the project piles, and
shall not be less than three. When various types of piles are adopted in the project, the test
quantity of each type of pile shall also not be less than two.
As for the point bearing pile and the long pile that is controlled according to the
structural strength of pile material, the standard value of the vertical bearing capacity of
clustered piles may be the sum of the standard value of the individual pile bearing capacity; as
for the friction pile, it may be determined according to the deformation controlling principle
(namely, taking the standard value of bearing capacity when satisfy the tolerable settlement
condition, which is equal to or less than the sum of the standard value of individual pile
bearing capacity).
4.6.8 Generally, the pile positions shall be arranged symmetric to the central line of column or
should be in square supporter quincunx. If arranged dissymmetricaly, the centroid of clustered
piles should be coincided with the gravity center of the resultant force of loads that act on pile
foundation for long period. The pile driving sequence shall also be considered when arranged
the piles.
One fundament should have at least three piles. If one foundation is only with two piles,
one joining beam perpendicular to the connecting line of two piles shall be set the grind slab
of pile top to contact with the neighboring grind slab, if one foundation is only with one pile,
then two-way joining beam shall be set to contact with the neighboring grind slab.
47
The length of the pile top embedding into the grind slab shall be determined according to
such factors as stressing condition of pile, design assumption and execution conditions, which
generally shall not be less than 50~100mm. The single-pile foundation, double-pile
foundation, single-row pile foundation, piles bearing up- pulling force or mainly bearing
horizontal force, raft plate and boxshaped grind slab as well as piles at periphery and critical
parts under the foundation of large-scale power equipment all shall be built-in the grind slab
and the main reinforcement in pile body shall be anchored into the grind slab as tensile
reinforcement. If required by structure, the protective layer at the four corners at pile top shall
be chipped away, and four steel reinforcements shall be welded and anchored into the grind
slab.
4.6.9 In the construction of pile foundation, the quality monitoring mode of pile shall be
determined based on the conditions of soil layer, pile making and sinking. The quantity of pile
in spot test is 5%~10% of the total amount of the project piles. The precast reinforced
concrete pile and pre-stressed tubular piles should adopt the lower limit, and the filling pile
should adopt the upper limit.
4.6.10 The earthwork excavated from the foundation pit of weak foundation shall be piled up
far away from construction area; the foundation pit should be kept dry and be poured for
foundation and backfilled as soon as possible. As for pit excavation in pile foundation project,
the setting time of the soil around pile shall be kept according to the requirement of design
documents. When the soil quality is poor, the groundwater level is high, the depth of
foundation is large and the stair excavation scheme and large-scale excavators are adopted,
the groundwater level shall be effectively dropped in the under-consolidated soil layer,
drainage consolidation of surface soil in foundation pit shall be facilitated to make the
foundation pit be dry, or other reliable construction measures may be adopted, and the
deflection condition of pile shall also be monitored in the construction period.
In all the projects of driven pile foundation, part of the piles shall be driven in at
extension section in advance (generally the pile shall be driven in for one spacing of
columns).
4.6.11 In weak foundation, the isolated foundation that may have displacement for bearing the
horizontal load generated in construction shall be set with joining beam in addition.
The bottom surface of joining beam shall be at the same elevation with the bottom of
grind slab, and the width of joining beam should not be less than 200mm. Its height may be
determined according to the calculation or may be1/10~1/15 of the centre-to-centre distance
of grind slab. Its steel reinforcement shall be anchored into the grind slab according to the
tensile requirement.
4.6.12 When the groundwater is erosive to the foundation concrete, erosion controlling
measures shall be adopted such as increasing the compactness of concrete, selecting
erosion-resistant cement or being painted with protective coating.
4.7 Underdrain
4.7.1 The underdrain design shall abide by the "protection with drainage" principle. The outlet
of all kinds of sewage shall be reasonably arranged to make them flow into the drainage
system of power plant without obstruction, the physical measures are as follows:
48
4.7.1.1 The drained water from the manufacturing and the overhauling of equipments and
pipelines are strictly prohibited to being directly drained into the cable trench or industrial
conduit.
4.7.1.2 The conduit of industrial water, cable trench, sluiceway and drain ditch must be
separated and intercrossed. The intercrossing principle shall abide by: The dry one gives way
to the wet one (as the cable trench gives way to sluiceway), the soft one gives way to the hard
one (as the cable trench gives to industrial water conduit), and the one by pressure gives way
to the gravity current one (as the industrial water conduit gives way to sluiceway). The
drainage system at intersections shall be mutually isolated, and the interstice shall be with
measures for preventing water seepage.
4.7.1.3 The free drainage shall be firstly considered. When trench, chasm and tunnel must
adopt the mechanical drainage, they shall be appropriately centralized in arrangement.
4.7.1.4 The outlet direction of the trench drainage from main workshop should adopt the
mode towards the outer side of turbine room or boiler house. The utility-type unit shall be in
unit of single machine and single furnace, the medium-and small-scale unit may be in unit of
two machines and two furnaces, the drainage should not be drawn out towards the extension
end.
4.7.1.5 The trench shall be set with longitudinal and transverse slopes. Longitudinal slope:
That of cable trench is not less than 5‰, and that of industrial water conduit is not less than
8‰, which may be separately reduced to 3‰ and 5‰ if the difficulty exists on arrangement.
The transverse slope is 1%~3%.
4.7.1.6 In the water treatment system, the trench for draining the acidic production sewage
shall be with acid protection measures. In limestone terrene, it shall pay special attention to
prevent the acidulous water from corroding the foundation.
4.7.2 As for the trench wall of the trenches indoors and outdoors, when adopting the openable
cover board, the stress condition in the operational phase and overhauling phase shall be
considered.
4.7.3 The earth pressure of trench wall may be calculated according to Coulomb Equation.
When the filling soil is clay soil and is tamped in layers, the equivalent internal friction angle
calculation may be adopted. Equivalent internal friction angle value: It may be 25°~30°at the
part above groundwater level when the trench wall is not higher than 4m. It may be 20°~25°at
the part under the groundwater level. The gravimetric density f soil may be the wet
gravimetric density.
4.7.4 The hydraulic bounded layer design of such underdrains as trench, pit and tunnel may
adopt different measures according to the three types of different levels of groundwater level.
The first kind is the maximum groundwater elevation is less than the bottom surface
elevation of trench;
The second kind is the maximum groundwater elevation is less than the bottom surface
elevation of trench, but the trench high requirement on moisture protection (such as the bare
bus bar tunnel);
The third type is that the maximum groundwater elevation is higher than the bottom
surface elevation of trench.
The structure types of the underdrains such as trench, pit and tunnel: The first kind may
adopt the brickwork setting or concrete structure, and the second and third kinds may adopt
49
the concrete or reinforced concrete structure.
The hydraulic bounded layer of underdrains such as trench, pit and tunnel: The first kind
may be treated according to common moisture protection, such as finishing by adopting
waterproof mortar; The second kind shall be coated with two layers asphalt or other
underwater paints at the bottom plate and outside of trench wall, and be coated with
waterproof mortar at inner wall; and the third kind generally may adopt the waterproof
concrete.
4.7.5 When adopting the waterproof concrete, the impervious grade of concrete is not less
than 6.S , the thickness of trench wall shall not be less than 250mm when being with
double-row reinforcing bars and not less than 200mm when being with single-row reinforcing
bars.
4.7.6 The indoor trench cover should adopt the steel-wire-net cement plate. The trench cover
at positions where are passed with automobiles in the overhaul site or indoors shall adopt the
reinforced concrete cover board. The outdoor trench should adopt reinforced concrete cover
board. All the reinforced concrete cover boards shall adopt the design with reinforcement at
both surfaces, and should be bounded with edges by adopting steel plate. The trench of
supporting cover board should be wrapped with angle steel at top. The trench cover board that
directly bears the wheel pressure of automobiles shall also have the recalculation on shearing
force.
4.7.7 The intervals among the expansion joints of concrete and reinforced concrete
underdrains and tunnels should be 30m indoors and 20m outdoors.
5 Dynamic machine foundations
5.1 Foundations of automobile unit and electric machines
5.1.1 This section is applicable to the frame foundation of steam turbine generator (electric
motor and rotary condenser) with working speed (n) above 1000r/min and not larger than
3000r/min. The foundation design of the bulk or wall-type electric machines or those with n
not larger than 1000r/min shall be implemented according to the relevant provisions specified
in "Code for Design of Dynamic Machine Foundation".
5.1.2 When designing the foundations of steam turbine set and electric machine, it shall be
closely cooperated with the manufacturer. The foundation design of new style machine set
shall be gone on hand in hand with the machine design with a view to considering integrally
for determining the rational foundation design scheme.
5.1.3 When identifying the dynamic behavior of steam turbine generator foundation, the
vibration condition of the foundation shall not be simply taken as the identification standard
and the internal relations between the vibrations of machine and foundation shall be analyzes
simultaneously.
5.1.4 The frame foundation shall be arranged independently, and the movement joint divided
from other structures shall be left around the top of the frame foundation. If necessary,
50
columns may set on the bottom plate of steam turbine set foundation for supporting the
platform of heater and the floor slab of basement.
5.1.5 The major structure of foundation should be arranged decoupling with the intermediate
platform. When it is difficult to arrange it by decoupling, proper measures shall be adopted to
reduce the amplitude of platform.
5.1.6 The strength grade of foundation concrete: That at bottom plate should not be less than
C15, and that at pillar and roof adopt C20~C30; the secondary grouting layer shall adopt the
pea gravel concrete that is one grade higher than that of roof in strength grade. Generally, the
steel reinforcement for foundation adopts the steel of grade I and II.
5.1.7 When the foundation is constructed on high or intermediate compressible foundations,
the permanent settlement observation points shall be separately set on the operating layer and
the ground benchmark post.
5.1.8 The dynamic load shall not be considered either in the calculation of the bearing
capacity of bottom plate or the checking of ground bearing capacity.
5.1.9 The recalculation on the bearing capacity of the foundation soil under foundation shall
comply with the requirement of the following equation:
fp 8.0 (5.1.9)
Where p——Design value of the static pressure at foundation base;
f——Design value of the ground bearing capacity calculated according to "Code for
Design of Building Foundation".
5.1.10 When designing the foundation, the integral gravity center calculated by the sum of
whole dead weight that is transferred onto the foundation and the weight of the foundation
itself shall be at the same vertical line with the centroid of foundation base as much as
possible. When the eccentricity is inevitable, the ratio between the offset value and the side
length of the foundation base that is parallel to the eccentric direction shall not be larger than
3%.
5.1.11 The frame foundation should be analyzed with various schemes according to the
multivariant space mechanical model to reasonably determine the structure type of foundation
(roof, column and bottom plate).
Generally, the structure type may be determined according to the following principle.
5.1.11.1 The roof shall be with adequate mass and rigidity. The mass of the element under the
application point of disturbing force shall be increased to decrease the vibration of foundation.
As for the tail part of foundation (where is initiator is located), the cross section of the
element at roof shall be increased appropriately for fear that the local vibration is oversize.
In order to keep the shaft line straight and even and improve the dynamic behavior of
foundation, the statical deflection of each transverse beam should be equal approximately.
The roof elements shall be stressed simply and reasonably. The longeron and transverse
beam shall avoid the eccentric load as much as possible with a view to decreasing the torque
force of coupled beam.
5.1.11.2 With preconditions meeting the requirements on strength and stableness, the rigidity
of column may be appropriately decreased, but the length-diameter ratio of the column should
not be larger than 14.
51
5.1.11.3 The bottom plate shall be with certain rigidity and shall be comprehensively
considered according to the rigidity and bearing capacity of the foundation.
5.1.12 The bottom plate of frame foundation may adopt shaft type, beam slab type or flatbed.
The thickness of the flatbed bottom plate of steam turbine set foundation or the beam
depth of the shaft type and beam slab type shall be determined according to the property of
foundation soil, which should not be less than 1/15 of the length of bottom plate.
5.1.13 When the foundation is constructed on the rock foundation, the rock formation shall
comply with the relevant requirements specified in the "Code for Design of Dynamic
Machine Foundation" or may adopt the anchor bar foundation or isolated foundation.
5.1.14 When the foundation soil is the clay with high or intermediate compressibility, the
rigidity of groundwork and foundation shall be strengthened and effective measures shall be
taken to reducing the differential settlement of foundation. When the foundation soil is of
high compressibility, the artificial foundation should ne adopted.
5.1.15 The cantilever platform of the foundation roof shall be made into solid web type, the
jib length generally shall not be larger than 1.5m, and the profile height at the cantalever
pedestal shall not be less than 0.75 times of the out-suspending length.
5.1.16 When the bottom plate is set one the soil aggregate and weathered bedrock foundations,
the influence of temperature effect in the construction shall b taken into consideration, and the
bottom plate shall be set with insulating layer under it.
5.1.17 In the construction, the may be set with two or three construction joints that shall be
separately set at column top, socle or near to the ground benchmark post.
The construction joint shall be treated, and steel reinforcements with diameter of 8mm,
interval of 200mm and length 600mm (being inserted into the concrete by 300mm) shall be
reserved on the concrete plane. Before the casting, the concrete plane shall be roughened,
cleaned and adequately wet, one layer of cement net slurry mixed with cementing agent shall
be made.
5.1.18 The power calculation of frame foundation may adopt amplitude of vibration method
(that is to take the amplitude value as the guideposts for design). The space multivariant
system should be adopted when calculating the amplitude. Generally, only the amplitude Az at
the vertical direction of the application point of disturbing force needs to be calculated. Az
shall comply with the requirements of the following equation:
AAz (5.1.18)
Where [A]——Allowable amplitude value (mm), see Table 5.1.18.
The disturbing force value adopted when calculating the amplitude shall be supplied by
the machine building plant, which may be selected according to Table 5.1.18 when the
information is unavailable. Table 5.1.18 Allowable Amplitude and Disturbing Force Value
Running rotation speed of machine(r/min) 3000 1500
Allowable amplitude A mm 0.02 0.04
Vertical and horizontal
transverse direction 0.20Ggi 0.16Ggi
Disturbing force Pgi at the ith
point when calculating
amplitude(kN) Horizontal longitudinal 0.10Ggi 0.08Ggi
52
direction
Notes: 1. The figures in the table are the allowable amplitude and disturbing force value when the machine is at normal
running.
2. Generally, Ggi, as the weight of the machine rotor at the ith point on foundation, is the rotor weight (kn) that
centralizes at beam and column top.
5.1.19 When calculating the amplitude, the peak amplitude within certain scope of running
rotation speed (generally is±25%) as the calculated amplitude with running rotation speed,
and shall be less than the allowable amplitude value specified in Table 5.1.18.
The calculated amplitude with 0~0.75 times of general range of work speeds shall not be
larger than 1.5 times of allowable amplitude value.
5.1.20 When calculating the amplitude, the disturbing force oiP at any rotation rate shall be
calculated according to the following equation:
2
0
n
nPP gioi (5.1.20)
Where oiP ——The disturbing force value (kN) at the ith point at any rotation rate;
giP ——The disturbing force value (kN) at the ith point at running rotation speed;
0n ——Any rotation rate (r/min);
n——Running rotation speed (r/min).
5.1.21 As for the frame foundation with running rotation speed (n) at 3000r/min, when
calculating the amplitude, the foundation may be considered according to rigidity (the effects
of anelasticity of foundation is not considered); the foundation with n not larger than
1500r/min should be considered with its elasticity, here, the rigidity factor of foundation may
be adopted according to the relevant regulations specified in the "Dynamic Machine
Foundation Design Code".
5.1.22 When there are actions of r disturbing forces, the amplitude 1A (mm) at the ith
particle shall be calculated according to the following equation:
1
2
k
Ar
A iki (5.1.22)
Where kiA ——The amplitude value of the kth disturbing force on the ith particle (mm).
5.1.23 When the foundation is the space frame composed of transverse frame and longeron
and the elasticity of foundation is not considered, it may be simplified as the transverse plane
frame and may adopt the simplified calculation by considering the two freedom systems with
space influence, or may be calculated according to the "Dynamic Machine Foundation Design
Code".
5.1.24 As for the home-made turbogenerator foundation with running rotation speed at
53
3000r/min, the foundation is space frame composed of transverse frame and longeron and
meets the conditions specified in Table 5.1.24, the power calculation may not be considered.
When it does not meet the conditions specified in the table, the power calculation should be
carried out according to the method specified in 5.1.18~5.1.23. Table 5.1.24 Conditions for Foundation without Power Calculation
Unit capacity
(MW)
Intermediate frame
Longeron
Side frame
≤125 giGGi 6 giGG 101
200 gii GG 7 giGG 121
Note: Gi is the weight centralizing onto the beam or column top (including the machine weight).
5.1.25 The bearing capacity of the members of turboset and electric machine foundations
shall be calculated according to the following loads:
Permanent load--Self-weight of member, machine weight, weights of other equipments
fitted on foundation and the cylinder expansion force, pipeline thrust force, vacuum pull force
of condenser, and the act of temperature difference;
Variable load--Dynamic load (or equivalent load) and live load of top plate;
Accidental load--Short-circuit moment; and direct-transmitted shock effect
5.1.26 When calculating the dynamic internal force of member, it may be calculated by
adopting the straight forward calculation with multivariant system or have the simplified
analysis according to the equivalent load.
The disturbing force for calculating the dynamic internal force, it shall be four times of
the dynamic internal force when calculating the amplitude and the influence of fatigue of
materials shall also be taken into consideration. As for the reinforced concrete member, the
endurance ratio pr
shall be 2.
Generally, the equivalent load at vertical direction may be assumed to be concentrated
load, and the equivalent load at horizontal direction may be assumed to act on the axial lines
of longeron and beam.
5.1.27 When calculating the dynamic internal force according to equivalent load, the basic
vibration mode and high modal contribution of foundation shall be respectively considered,
the dynamic internal force shall be calculated according to the following provisions and shall
take the larger value as the controlling value.
5.1.27.1 When calculating dynamic internal force according to the basic vibration mode of
foundation, the equivalent load shall be calculated according to the following equation:
(1) The equivalent load NZi at the ith vertical direction on transverse frame shall be
calculated according to the following equation, and shall not be less than four times of rotor
weight.
max42
1
n
nPN gipzi (5.1.27-1)
Where: n1——The first natural vibration frequency (r/min) of transverse frame at vertical
direction shall be calculated according to "Dynamic Machine Foundation Design
54
Code".
ηmax——Maximum power coefficient, which adopts 8.
As for the turbo-unit with running rotation speed at 3000r/min, when no power
calculation is required, the vertical equivalent load shall be adopted according to Table
5.1.27-1. Table 5.1.27-1 Vertical Equivalent Load
Power of machine
unit(MW)
≤25 >25 and ≤125 200
ziN(kN)
10Ggi 6Ggi 4Ggi
(2) The total equivalent load at horizontal direction (is Nx at transverse direction and Ny at
longitudinal direction) shall be calculated according to the following equation, and shall not
be less than the gross weight giG
of rotor. The total equivalent load shall be distributed
onto each frame according to rigidity.
pxjd
gix K
G
GxN (5.1.27-2)
pyjd
giy K
G
GyN (5.1.27-3)
Where εx, εy——They are the calculation coefficients (m) at transverse direction and
longitudinal direction, as for the unit with n=3000r/min, 8.12x 10-4,
4104.6 y ; As the unit with n=1500r/min, 41040 x ,
41020 y ;
dG ——The whole permanent load at top plate of foundation (including the
self-weight of top plate, weight of equipment and half of the pillar weight) (kN);
pxjK, pyjK ——The total rigidity in horizontal direction of the jth frame in transverse
direction and longitudinal direction of the foundation (kN/m).
As for the turbo-unit with running rotation speed at 3000r/min, when no power
calculation is required, the total equivalent load in horizontal direction shall be adopted
according to Table 5.1.27-2. Table 5.1.27-2 Total Equivalent Load in Horizontal Direction
Unit capacity (MW) ≤25 >25 and ≤200
Nx, Ny(kN) giG2 giG
(3) The design schedules shall be respectively adopted according to Figure 5.1.27-1 and
Figure 5.1.27-2.
55
Figure 5.1.27-1 Design Schedule of Transverse Directional Frame
5.1.27.2 When considering the vibration effect of the high vibration mode of foundation, the
beam and longeron of top plate shall be calculated for dynamic internal force according to the
equivalent load specified in Table 5.1.27-3 and the corresponding design schedules (Figure
5.1.27-3 and Figure 5.1.27-4).
Figure 5.1.27-2 Design Schedule of Longitudinal Directional Frame
Table 5.1.27-3 Equivalent Load by Considering Influence of High Vibration Mode
Direction Vertical direction Transverse direction Longitudinal direction
Load (kN) cizi GN 8.0 cixt GN 8.0 ciyi GN 4.0
Note: Gci is the self-weight of member and the machine weight (distributed equally or concentratedly) it supports.
Figure 5.1.27-3 Design Schedule of Beam
56
Figure 5.1.27-4 Design Schedule of Longeron
5.1.28 When calculating the dynamic internal force according to the multivariant system of
space, the maximal dynamic internal force value with in the scope of 1.25 times of running
rotation speed of machine shall be taken as the controlling value.
When r disturbing forces act, the dynamic internal force Si at the ith material particle shall
be calculated according to the following equation:
r
kiki SS
1
2
(5.1.28)
Where ikS ——The dynamic internal force generated by the kth disturbing force at the ith
point.
5.1.29 The calculation for the bearing capacity of the foundation elements shakk be
assembled according to the undermentioned load effect;
Basic assembly——It is assembled by permanent load and dynamic load (or equivalent
load), the dynamic load is only considered with the one-way action and it assembly
coefficient is 1.0.
Occasionla assembly——The assembly of permanent load, dynamic load and
short-circuit torque, the assembly coefficient of dynamic load is 0.25, and the assembly
coefficient of short circuit torque is 1.0.
Direct-transmitted shock effect——It is assembled by permanent load, dynamic load and
direct-transmitted shock effect, the assembly coefficient of dynamic load is 0.25, and the
assembly coefficient of direct-transmitted shock effect is 1.0.
5.1.30 The longeron and crossbeam of foundation roof shall be considered with the stress
generated by the temperature difference at both sides of element, generally, the temperature
steels shall be separately placed at both sides of the beam, and the steel ratio at each side may
reach 0.1%, but when the unit capacity is larger than or equal to 100MW, the steel ratio at the
longitudinal beam side face of its high and intermediate-pressure component side shall be
increased to 0.15%.
When the length of longitudinal framework of foundation is larger than or equal to 40m,
it shall be calculated according to the temperature effect of longitudinal framework. The
57
calculated temperature difference at roof and socle may be 20℃ when the information is
insufficient.
5.1.31 When the mobile load of roof is only used at equipment installation, the strength of
roof shall be determined according to the process requirements, which should be adopt
20~30kN/m2.
5.1.32 The partial factor of permanent load may be 1.2, the variable partial load factor may be
1.4, the partial factor of accidental load may be 1.0, and the partial factor of direct-transmitted
shock effect may be 1.3.
5.2 Auxiliary machine foundation
5.2.1 The section is applicable to the auxiliary machine foundation that is constructed on
groundwork (hereinafter referred to as auxiliary foundation).
5.2.2 The infrastructure mode shall be determined according to the functions and capacity of
auxiliary machines, the requirements of manufacturer and the different conditions of
groundwork, which may separately adopt foundation, wall-type and frame foundation.
5.2.2.1 The foundations of draught fan and blower may be designed into massive foundations.
When the capacity of electric motor is above 2000kW, they may be designed to wall-type or
frame foundations.
5.2.2.2 The tube mill foundation may be designed into massive foundation or the wall-type
and stump foundations with common bottom plate, and it may be designed into frame
foundation when the conditions pertmit. When the groundwork is with good conditions (fk is
not less than 250kPa and the differential settlement is very small), it may be designed inyo
isolated foundation with the fore and after bearings separated, but the rotating part and the
large cone bearing must be at the same foundation mat.
Other coal mill foundations should be designed into the massive foundation.
5.2.2.3 The foundations of electrically driven feed pump with motor capacity above 2000kW
and the steam feed pump with motor capacity above 2000kW should be designed into wall
type or frame foundations
5.2.2.4 The coalbreaker foundation may be designed inyo independent wall-type or frame
foundations.
5.2.2.5 Except the forementioned achine foundations, other auxiliary machine foundations
may be designed into massive foundations.
5.2.3 The auxiliary machine foundation should not be connected with the building foundation.
When the tube mill foundation is pressing above the foundation of main workshop framework,
proper vibration isolation measures should be adopted (as rubber blanket or sand bedding
course). When the foundations of other auxiliary machines (such as blower fan, fan mill,
medium-speed coal grinding mill, and feed water pump) must prees above the building
foundation, proper effective vibration isolating measures (such isolation mountings as steel
spring and rubber) shall be adopted. When calculating the foundation of main workshop,
those additional loads must be counted in and the differential settlement shall be taken into
consideration.
5.2.4 The auxiliary machine foundations such as draught fan, blower, coal grinding mill
coalbreaker, electrically driven feed pump and steam feed pump with motor capacity above
58
100kW should be placed on the raw soil groundwork. When the arrangement permits, the
basal area of foundation may be increased with condition that not increases the concrete
volume.
Figure 5.2.5 Schematic Diagram for Allowable Elevation Difference of Neighbouring Foundations
5.2.5 when the bottom elevations of the auxiliary machine foundation and neighbouring
foundations are different (as Figure 5.2.5), the following equation shall be met
BtgA (5.2.5)
Where ——Internal friction angle of soil, plain concrete or rubble concrete underlayer
may be set under the foundation when the equation is not met.
5.2.6 The auxiliary machine foundation with motor capacity less than 100kW may be plaved
on the tempered backfilling soil. The treatment of backfilling soil must comply with those
specified in related codes.
5.2.7 The foundations of electrically driven feed pump, steam feed pump, initiator and all
kinds of centrifugal pumps with rotation speed above 1000r/min and not larger than
3000r/min and the power less than 2000kW, if they are massive foundations with weight
larger than five times of machine weight or the wall foundations meeting those specified in
Table 5.2.13, may have no power calculation (excluding the machine foundation with variable
speed).
5.2.8 The power calculation of the massive and wall foundations with the rotation speed of
equipment not larger than 3000r/min shall be carried out according to the relevant provisions
specified in "Code for Design of Dynamic Machine Foundation" (hereinafter referred to as
"Code for Dynamic"), the machine foundation of general type may be simply calculated
(excluding the foundation of equipment with variable speed) according to Equation
(5.2.10-1).
The power calculation of framework machine foundation with the running rotation speed
of equipment not larger than 3000r/min shall be carried out according to the relevant
provisions specified in "Code for Dynamic".
5.2.9 The wall and frame foundations of independent coalbreaker shall have power
calculation according to the corresponding provisions specified in the "Code for Dynamic".
When the independent wall foundation of coalbreaker with production output below 300t/h
meets those specified in Table 5.2.13, it may not have the power calculation.
The massive and wall foundations of tube mill may not have the power calculation.
59
5.2.10 When the wall and massive foundations with the rotation speed of equipment not larger
than 1000r/min have simple calculation, only the maximal lateral and horizontal amplitude at
the upper margin of foundation shall be calculated, and the vertical amplitude may not be
calculated. The design schedule of massive foundation is showed as Figure 5.2.10.
The horizontal amplitude xA
of foundation at the top surface shall be calculated
according to the following equation:
h
K
HP
K
PA x
x
xx (5.2.10-1)
21
22
1
2
21
2
41
1
xD
(5.2.10-2)
22
221
1 hK
K x
x
(5.2.10-3)
m
K xx 2 (5.2.10-4)
Where 1 ——The horizontal natural vibration frequency of the approximate first principal
mode of foundation (rad/s);
H——Distance from the rotating main shaft of man machine to the foundation base (m);
h——Height of foundation (m);
1xD ——The damping ratio of the horizontal rotation toward the first vibration mode,
which shall be taken value according to those specified in "Code for Dynamic";
——The working circular frequency of machine (rad/s), =0.105n (one harmony);
n——Running rotation speed of machine (r/min);
h2——Distance from the foundation base to gravity center of foundation (m);
Kx——Shear stiffness of groundwork (kN/m);
K ——Flexural rigidity of groundwork (kN·m);
60
Px——Horizontal disturbing force of machine (kN);
xA ——Horizontal amplitude at top surface of foundation (m);
——Amplification coefficient;
x ——Horizontal self-oscillation circular frequency of base cluster (rad/s);
m——Total mass of the foundation and equipment (t).
5.2.11 The disturbing force or excentricity of the machine shall be supplied by the
manufacturers. And they may be selected by referring to Table 5.2.11 if the information is
insufficient.
g
Gm 0 in the table, m is the mass of machine or the rotating part of electric motor, G0
is the gravity of the machine or the rotating part of electric motor, and g is the acceleration of
gravity.
5.2.12 The power calculation of the auxiliary machine foundation with running rotation speed
not larger than 3000r/min shall comply with the following conditions:
zz AA (5.2.12-1)
xx AA (5.2.12-2)
Where: Az and Axφ are the vertical horizontal amplitudes at the application point of calculated
disturbing force or at the top surface of foundation, [Az] and [Axφ] are the maximal allowable
vertical and horizontal amplitudes.
The maximal allowable amplitudes [Az] and [Axφ] shall be adopted according to Table
5.1.12 if this information is unavailable.
5.2.13 The wall foundation with power calculation according to the calculation principle of
massive machine foundation should have rigid connection of its vertical and horizontal walls
with roof, bottom plate to assure their joint work. Due to the process requirements, only the
one-way wall is set, the wall shall be set parallel to the acting direction of horizontal
disturbing force. The structure dimension of wall foundation may be adopted according to
Table 5.2.13. Table 5.2.11 Excentricity and Disturbing Force of Main Subsidiary Foundation
No. Nomenclature of
machinery
Name of the moving
part of machine
Rotation speed of
machine (r/min); Excentricitye0 (mm)
Disturbing
force P0
1 Blower Impeller 0.5~0.7
2 Draught fan and mill
exhauster Impeller 0.7~1.0
3 Fan mill Impeller
4 Impact breaker Rotor
1.0~1.5 of soft coal and
1.5~2.0 of hard coal
5 Plate hammer crusher Rotor 1.0
6 Ring crusher Rotor 0.6~1.0
7 Pumps Impeller n≥1500 0.1
8 Pumps Impeller n =1000 0.2
P0=me0ω2
61
9 Pumps Impeller n<1000 0.25~0.5
Note: The unit of disturbing force P0 is N or kN, where the unit of e0 is m.
Table 5.2.12 Maximal Allowable Amplitude of Foundation
Allowable amplitude value(mm) Foundation name Running rotation speed(r/min)
Vertical(Az) Horizontal (AxФ)
Blower fan, pumps, fan mill 3000
1500
1000≥n>750
750≥n≥500
n<500
0.03
0.06
0.10
0.15
0.20
Coalbreaker 300<n≤750
750<n
0.15
0.10
0.20
0.15
Note: The allowable amplitude value of the equipment foundation of 3000r/min and 1500r/min is the requirement on
frame foundation.
5.2.14 The wall foundation is connected with vertical and horizontal walls, and has rigid
connection with upper roof and bottom plate to keep certain rigidity. And its dimension is
adopted by referring to Table 5.2.14.
5.2.15 Reinforcement requirement of massive foundation: The whole foundation may not be
set with steel reinforcement nut only partially set with constructional reinforcement near to
the bolt hole when the volume is less than 40m3; the whole foundation shall be set with
constructional reinforcement when the volume is larger than 40m3; as for the weak positions
such as superstructure or pore space, necessary steel reinforcements shall be set in addition no
matter the size of volume. The specific requirements of reinforcement shall be implemented
according to the relevant provisions specified in the "Code for Dynamic". Table 5.2.13 Structure Dimension of Wall Foundation
Element name of foundation Element size of foundation
Upper top plate Flat plate ≥0.5m
Ribbed slab ≥0.15m
Jiblength of top plate ≤1.5m
Profile height of top plate at pedestal of
cantalever ≥
3
1of jiblength
Wall thickness When the wall is parallel to horizontal disturbing force, it≥
6
1 of clear height
and≥0.5m
When wall is perpendicular to horizontal disturbing force, it≥4
1 of clear
height
Thickness of foundation mat ≥0.6m, and≥ wall thickness
Jiblength of bottom plate Plain concrete bottom plate≤thickness of bottom plate
Reinforced concrete bottom plate≤2.5 times of the thickness of bottom plate
Table 5.2.14 Physical Dimension of Wall Foundation
Element name of foundation Element size of foundation
Wall thickness
Thickness of foundation mat ≥0.5m, ≥
6
1
of the clear height of wall
62
Jiblength of bottom plate at foot foundation
Jiblength of upper top plate
Thickness of upper horizontal top plate
Profile height at upper cantalever and beam support part
≥0.6m
≤2.5 times of the thickness of bottom plate
≤1.5m
≥0.1m
≥3
1
Of the extension elongation of cantalever
5.2.16 When determining the dimension of auxiliary machinery foundation according to the
technological information, the following requirements shall also be complied with:
5.2.16.1 The horizontal distance from the edge of auxiliary foundation to edge of foundation
should not be less than 100mm.
5.2.16.2 The distance from the axial line of concealed anchor bolts to the edge of foundation
shall not be less than four times of the bolt diameter, the clear concrete thickness bellow the
bottom surface of concealed anchor bolts shall not be less than 50mm.
5.2.16.3 The distance from the edge of anchor bolt box to the foundation edge shall not be
less than 100mm (including the clear distance of such edges of pore space and hollow of the
foundation); otherwise, the constructional reinforcements must be partially set and be
strengthened. The clear distance from bottom of anchor bolt box to the foundation bottom
shall not be less than 100mm.
5.2.16.4 The cross dimension of anchor bolt hole should be 5~6 times of the diameter of
anchor bolt. The depth (except the thickness of secondary grouted layer) should be the buried
depth of anchor bolt added by 100~150mm. When the pore space depth exceeds 500mm and
the bottom hole is above ground, the sundries cleaning hole should be set.
5.2.17 Burring requirement of anchor bolt: The burring requirement of the anchor bolt of
auxiliary machinery foundation shall be supplied by the machine building plant or by the
process designer. As for the anchor bolt of weighted machine such as hook machine, the
buried depth shall not be less than 20 times of the diameter of bolt; the buried depth of
anchor-slab-type buried depth shall not be less than 15 times of the diameter of bolt.
6 Fuel buildings
6.1 Coal-fired buildings
6.1.1 As for the longitudinal beam directly bearing the mobile load of train in the coal
discharging building, the design load shall adopt the mobile load specified in railway
standards of the People’s Republic of China, that is, the "moderate—mobile load". The
structural design and calculation must comply with those specified in the "Code for Design on
Railway Bridge and Culvert".
6.1.2 The structure selection and design schedule of underground structure should be selected
according to the following principles.
6.1.2.1 Requirement on structure selection of dump chamber
(1) Generally, when setting two rotor type or rotaside tippers, the reinforced concrete
round or box construction may be adopted.
63
(2) Generally, when setting one rotor type or rotaside tippers, the reinforced concrete
round or box construction may be adopted.
When the underground structure adopts open caisson scheme, it shall comply with those
specified in the "Technological Provisions of Hydraulic Design in Thermal Power Plant".
6.1.2.2 Requirement on structure selection of slot-type coal chute
(1) When there is no groundwater influence, the sidewall and bottom plate may adopt
block casted or assembling reinforced concrete structure, and the mode of bottom plate may
also adopt slab rib type or separate type.
(2) When there is groundwater influence, the sidewall bottom plate shall adopt the block
casted reinforced concrete structure.
6.1.2.3 Requirements on structure selection of underground coal delivery tunnel:
(1) When there is no groundwater influence, the top plate and sidewall should adopt
reinforced concrete structure; and when the tunnel is shallow, they may also adopt the
concrete or rubble concrete structure.
(2) When there is groundwater influence, they shall adopt the reinforced concrete box
construction.
6.1.2.4 Selection principle of design schedule:
(1) Generally, the subsurface constructions are space structures, they may be simplified
into longitudinal and transverse plane structural system for analyzing the internal force, be
adopted with linking solution or decomposition calculation.
The structure selection and design schedule of common tippler chamber and slot-type
coal chute see Annex D.
(2) If the skew wall of the coal scuttle of tippler chamber and slot-type coal chute is
supported on the terrestrial platform and coal feeder platform together with the bottom
sidewall of basement, when calculating the sidewall, the platform may be taken as the
horizontal elastic bearing point, but the platform plate must be calculated two-way bending
member.
In the calculation, the influence of the elastic deformation of framework column in
sidewall shall be taken into consideration, the coefficient of reaction at supporting point of the
platform plate of coal feeder generally is 0.8~0.9.
6.1.3 When calculating the bearing capacity of the train crossbeam in the coal discharging
building, the train load shall be multiplied by the impact coefficient (1+μγ) after deceleration.
The equation is
VV
V
l kp230
6211 (6.1.3)
Where l——Span of beam (m);
V——Design running speed, which may be V=15km/h;
kpV ——Terminal speed, which may be km/h65kpV .
When calculating the bearing capacity of the crossbeam that directly supports the tippler,
the vertical and horizontal loads shall be multiplied by the power coefficient. This coefficient
shall be supplied by the technical design specialty, or may be adopted according to Table 6.1.3
if the information is unavailable. The vertical and horizontal force generated by the equipment
64
shall be implemented according to the relevant provisions of manufacturer Table 6.1.3 Power Coefficient of Tippler Load
Power coefficient Categories of tipplers
Vertical Horizontal
Rotaside type
Rotor type
1.5~2.0
2.5
1.5~2.0
2.0~2.2
6.1.4 The waterproofing design of subsurface construction shall be designed according to the
"Waterpoof Technical Specifications for Underground Works".
6.1.5 The indoor terrace of subsurface construction must be set with drainage slope, drain
ditch and collecting well. The longitudinal slope of drain ditch shall not be less than 0.5%,
and the transverse slope shall be 1%~3%. The slope aspect shall be determined according to
the positions of ditch and well.
6.1.6 The load effect assembly of subsurface construction shall be implemented according to
those specified in the chapter on load, and the following provisions are supplemented, the
loads are classified into:
6.1.6.1 Permanent load (dead load), such as dead load, fixed equipment, earth load, earth
pressure and water pressure.
6.1.6.2 Variable load (mobile load), such as coal weight and the load of train, automobile and
coal transporter.
(1) Variable load of train: when the railways are of two lines, if the twolines entering into
the tippler chamber are all coaler mobile load, and the two lines entering into the slot-type
coal chute are all engine mobile load, the load acting on the frame girder shall be multiplied
by the reduction coefficient 0.9. In particular cases, if it is designed according to that the
engine does not enter into the slot-type coal chute, the marks for prohibiting the engine
passing shall be set.
(2) Variable load in coal scuttle of slot-type coal chute: The coal scuttle shall be filled
with coal that is higher than the coal scuttle by 0.5~1.0m. When it is multi-hole coal scuttle,
the worst assembly of no-load and full-load of coal scuttle shall be taken into consideration.
(3) Variable load of coal transporter: when the coal transporter transporting coal from the
coal yard to ground reception bunker, the pressure effect of the load of coal transporter on the
sidewall, coal grate, and coal scuttle wall shall be taken into consideration.
6.1.7 The coal transporting trestle shall be selected according to the relevant provisions
specified in the "Technical Specification for Design of Thermal Power Plants". The
lightweight construction should be adopted when it is arranged sealed. The lateral truss of
trestle adopts steel structure, reinforced concrete or prestressed reinforced concrete structure.
6.1.8 When the coal transporting trestle is designed according to reinforced concrete
articulated reinforced concrete trestlework, the maximal space between the expansion joints
may be adopted according to the following provisions:
Enclosed trestle 130m
Open trestle 100m
When the length of trestle exceeds the maximal space of expansion joints specified
above, the temperature effect of the trestle column shall be recalculated.
6.1.9 The trestle must with adequate space rigidity and shall comply with the following
requirements:
65
6.1.9.1 When adopting trestle as the sidewall framework, the crossbeam and the montants at
two ends of trestle shall be made into∏-shaped rigid frame at top to assure the lateral stability
of trestle (Figure 6.1.9).
Figure 6.1.9 Trestle-type Sidewall Framework
The transverse wind power of trestle shall be bear by the longitudinal horizontal bracings
at upper and lower cambers. This horizontal bracing shall be set along the whole trestle.
6.1.9.2 The upper longitudinal bracing shall be set along the overall length of through truss,
the transverse vertical bracing shall be set simultaneously, their quantity may be determined
according to the span size of trestle, but shall not be less than two in each span.
6.1.9.3 The trestle adopted precast reinforced concrete thin webbed girder, when one end is
supported on the column or beam of coalbreaker chamber or transfer site, the lateral
horizontal bracing shall be set at the head end of flange for assuring the stableness of thin
webbed girder at upper end.
6.1.10 Supporting requirement of trestle truss (or beam):
When the trestle is supported on the pedestal of main workshop framework or side
column, the pedestal shall be designed into roller pedestal, and the one near to coalbreaker
chamber shall be articulated fixedly.
When the trestle and plant are separated, one end is of fixed articulation; the other end
shall be made into cantalever and shall be separated from the plant and coalbreaker chamber.
It shall be fixed articulation at the intermediate span and the two ends.
6.1.11 The node structure of movable hinged support of trestle should adopt roller pedestal.
6.1.12 Computational length of the trestle column:
l0=1.25Hc of the bottom column perpendicular to the coal belt direction;
l0=1.5Hc as for the rest column layers;
l0=1.25H at the direction parallel to the coal belt.
Where Hc ——Distance from the top surface of foundation to the center of beam or the
distance among central lines of beams;
66
H——Distance from the top surface of foundation to the bottom of the pedestal of
trestle.
The profile height of trestle column general is H/25~H/20.
6.1.13 The beam directly supporting the coalbreaker must have the calculation on the vertical
vibration and the bearing capacity of cross section.
At regular production operating conditions, the maximal allowable amplitude value
(single ampitude) of the vertical vibration of floor slab structure generally is 0.08mm.
6.1.14 The calculation for the amplitude value of the floor slab of coalbreaker may be carried
out according to the beam-type design schedule.
The maximal allowable excentricity 0e of the rotor of coalbreaker shall be supplied by
the technological design specialty, and may be adopted according to Table 5.2.11 if the
information is unavailable.
6.1.15 The calculation for the crosssectional bearing capacity of the beam that bears dynamic
load may adopt the static calculation method by multiplying the equipment load with power
coefficient. The load shall be calculated as:
P=βQ (6.1.15)
Where β——Power coefficient of coalbreaker, which shall be taken value according to the
rotation speed of coalbreaker, β=5.0 when the rotation speed is at or above
740r/min, otherwise, β=4.0;
Q——Load of all equipments (kN).
6.1.16 The beam that directly supports the coalbreaker may not have calculation on vertical
vibration when its height-to-span ratio meets the value specified in Table 6.1.16.
67
Table 6.1.16 Height-to-span Ratio of Beam (h/l)
5<l≤6 6<l≤7 7<l≤8 8<l≤9
One Two One Two One Two One Two
2515 0 P
3525 0 P
4635 0 P
6
1
2.5
1
8.4
1
5.5
1
7.4
1
5.4
1
5.5
1
5
1
7.4
1
5
1
5.4
1
2.4
1
5.5
1
5
1
7.4
1
5
1
5.4
1
2.4
1
5.5
1
7.4
1
5.4
1
5
1
2.4
1
1.4
1
Notes: 1. The width-to-depth ratio of beam generally shall meet3
1/ hb ;
2. The strength grade of concrete shall not be less than C20, and the steel reinforcement shall be of grade II;
3. It shall be treated according to 6.1.22 when kN460 P ;
4. See table 5.2.11 for the calculation equation of the disturbing force P0 of coalbreaker.
6.1.17 The coalbreaker chamber may adopt reinforced concrete frame structure or adopt the
composite structure of bearing brickwall and site-casted beam slab.
The coalbreaker must be arranged on the beam to make the disturbing force direction be
accored with the X-direction of beam. The arrangement of floor slab shall avoid the
cantalever.
6.1.18 The beam slab of coalbreaker floor shall adopt the monolithic reinforced concrete
structure, and the thickness of floor slab shall not be less than 120mm.
6.1.19 As for the walking beam bearing dynamic load, both the beam tip and beam bottom
shall be set with reinforcing bar, and the critical steel ratio shall not be less than 0.15%.
The beam stirrup shall adopt enclosed steel hoop, its diameter shall not be less than
8~10mm; when the beam depth is larger than 2m, the diameter shall not be less than
10~12mm; the bar spacing shall not exceed 200~300mm.
6.1.20 The coalbreaker coal balance room shall be set with vibrationproof slot. The
coalbreaker that is supported onto the floor slab should be adopted with isolation mounting if
the condition permits.
6.1.21 the following structural measures should be adopted for reducing the influence of the
vibration of coalbreaker.
6.1.21.1 The composite structure adopting brickwall for bearing load shall be set with ring
beam at each layer. At the connection part of walls, three horizontal reinforcements with
diameter of 6mm shall be set for every five bricks.
At the crossbeam pedestal that directly bears dynamic load, the reinforced concrete
Girder span l ( m )
Quantity Disturbing
force of
coalbreaker (kN)
68
cushion block shall be set and the arranged at two directions with mat reinforcement with
diameter of 8mm and space of 100mm.
6.1.21.2 When filling by adopting the supporting brickwall of reinforced concrete frame
structure, the drawknot among wall, beam and column may be treated according to the
requirement on anti-seismic construction of building.
6.1.22 The supporting structure of the coalbreaker with dynamic disturbing force above 46kN
may adopt independent wall type or framework type foundations, and movement joints shall
be set around its top to separate it from the floor slab structure.
6.1.23 The gantry crane and stacker-reclaimer foundations may adopt reinforced concrete and
concrete structures according to the different types of foundation soil.
6.1.24 The computation module of ground foundation may adopt the elastic bedding value
method or shearing force balance method for the calculation on internal force of foundation.
6.1.25 The foundation beams of gantry crane and stacker-reclaimer shall be designed
according to the medium-grade working system, the fatigue recalculation may be omitted, and
the value of power coefficientβ shall be supplied by the technologicl design speciality.
6.1.26 The foundation structure may adopt strip stiffening bar foundation. When it is
reinforced concrete foundation, the reinforcement ratio should not be less than 0.1%; the
vertical horizontal reinforcement with diameter of 8~10mm shall be set within the height
scope web of girder, the space shall not be larger than 500mm; the hooped reinforcement
should adopt the enclosed steel hoop, the diameter shall be 10mm and the space shall not be
larger than 300mm. When it is concrete foundation, the constructional reinforcement shall be
placed at the tensile area of concrete, and the reinforcement ratio shall not be less than 0.05%.
6.1.27 The design of round silo shall comply with the following requirements:
6.1.27.1 The plan layout of silo shall be determined according to such conditions as
technology, torography, engineering geology and construction after the technical-economic
comparison.
6.1.27.2 The group silo should adopt the connecting type with the excircle of bulkhead be
tangential. The round silo with diameter larger than or equal to 18m should adopt independent
arrangement mode (excluding the rock foundation). The expansion joints shall be set when
the total length exceeds 50m.
6.1.27.3 When round silo with diameter larger than 15m is set with high-capacity motor (not
less than 100kW) at its top, the vibration calculation is required, the vertical allowable
amplitude is not larger than 0.04mm (single amplitude), and the site-casted reinforced
concrete silo top structure shall be adopted.
6.1.28 The wall thickness of round silo generally is
0100t
dt n (6.1.28)
Where t——Wall thickness (mm);
t0——t0=100mm when the diameter of round silo is equal to or less than 15m;
t0=120mm when the diameter of round silo is equal to or larger than 16m;
dn——Internal diameter of round silo (mm).
6.1.29 In power plant, the structure type of the coal silo bottom shall firstly adopt the
interstice-type full-length or ring-shaped headwall and the conical funnels arranged
69
symmetrically.
6.1.29.1 The thickness of horn type headwall may adopt 1/20~1/30 of the span at short side.
6.1.29.2 The wall thickness of the interstice-type bottom plate may adopt 1/5~1/10 of the
jiblength of bottom plate.
6.1.30 The lower supporting structure of the round silo should adopt the integral connection
of silo wall and funnel, and the joint supporting type of silo wall and inner column (Figure
6.1.30 (a)); it may also adopt the non-integral connection of silo wall and funnel or the joint
supporting type of inner wall and inner column (Figure 6.1.30 (b)).
Figure 6.1.30 Schematic Diagram of Under-silo Supporting Structure
(a) Supporting mode of silo wall and inner column; (b) Supporting mode of inner wall and inner column
6.1.31 The round silo foundation may adopt round and ring plate foundation or slab raft
foundations, or the assembled foundation of shallow-spherical shell and ring plate.
6.1.32 The top of round silo may adopt site-casted or fabricated bar concrete structure; when
the diameter is equal to or larger than 15m, it may adopt the reinforced concrete abscissus
cone shell and shallow-spherical shell structures; when the diameter of silo is greater than or
equal to 18m, the silo top structure may adopt steel structure framework and light enclosure
wall.
6.1.33 When the round silo is set with eccentrical coal outlet or many coal outlet at the bottom,
the adverse effect of eccentric discharging of coal shall be taken into consideration.
The added value △ph (kPa) of horizontal pressure when discharging coal eccentricaly
may be calculated according to the following equation:
n
vh R
ep.p 0250 (6.1.33)
Where e0——Excentricity, which is the distance (m) from the central line of silo to the central
line of coal outlet.
Rn——Internal diameter (m) of the net section of silo;
pv——The design value (kpa) of the vertical pressure on unit area at silo bottom must be
calculated according to the Equation (3.2.2-2) specified in the "Code for Design
of Reinforced Concrete Silos" (hereafter referred to "Code for Silos"), the
correction coefficient of vertical pressure cv=1.0;
△ph——Assuming that the added value △ph is evenly distributed along the circle, △ph
is a constant within hn/3 bellow the calculated altitude (hn) of stored coal, and
70
shrinks to zero in straight line above this scope, see Figure 6.1.33.
When the eccentricity moment e0<0.2R, the adverse effect of discharging coal
eccentrically may not be considered.
6.1.34 The calculation for the top, wall and bottom structures of round silo shall comply with
those specified in the "Code for Silos".
Hoop tension of silo wall:
Hoop tension 0N (kN/m) at any depth s
RphphN )(0 (6.1.34-1)
Where hp ——The horizontal pressure (kPa) of coal on unit area of silo wall must be
calculated according to those specified in "Code for Silos";
R——Radius of round silo (m);
µ——Amplification coefficient,μ=1.3 within 6nh
scope at the silo top and μ=1.0 within
the scope of nh6
5;
Figure 6.1.33 Distribution for the Added Value of Pressure on iNner Wall of Silo
nh ——Calculated altitude of stored coal (m)
Vertical pressure of silo wall:
With action of load at silo top and the deadweight, the vertical pressure )m/kN(1N on
the cross section of silo wall of unit perimeter is
nd
GN
1 (6.1.34-2)
Where G——Dead load above the calculated cross section and the load on silo top (kN).
71
The vertical pressure N2 (kN/m) resulted by the coal generating friction force is
)(42 v
n psd
N (6.1.34-3)
Where ——Gravimetric density of bin stock (kN/m3);
s——Depth of calculated cross section (m);
pv——Vertical pressure (kPa) acting on unit area at s section.
Hoop bending moment of silo wall:
The hoop bending moment may be calculated according to the following equation by
considering the non-axial symmetry distribution condition of coal pressure along hoop
direction:
Mθ=0.01phR2 (6.1.34-4)
Vertical bending moment of silo wall:
When the silo wall and interstice-type headwall are connected integrally, the horizontal
force action of headwall on silo wall shall be condsiered, and the internal force at the
connecting part shall be calculated for the edge effect.
6.1.35 The strength calculation structure requirement of the opening of round silo shall be
designed according to the "Code for Silos"; the opening of the silo with diameter larger than
15m may be calculated according to the Annex E of this stipulation.
6.1.36 The horizontal included angle of the headwalls at silo bottom shall not be less than 60°,
the inner lining materials may adopt the cast stone plate or steel shot, and the surface shall be
even and smooth.
6.1.37 The dry coal shed should adopt the reinforced concrete column structure and light roof
cover system. The dry coal shed with span larger than 36m should adopt bow member and
wire frame.
6.1.38 The adverse effect of the coal piled in the dry coal shed on the foundation and
superstructure shall be taken into consideration.
6.2 Fuel oil buildings
6.2.1 The foundation of the overground steel oil tank should adopt sand bedding course above
the raw soil, and its top surface shall be paved with bituminous sand as insulating layer. The
center of tank foundation shall be thicker than the part around it for fear that the center is
accumulated with oil and water after ground subsidence that can not be drained away.
As for the steel oil tank with capacity not larger than 500m3, when not setting the loop
retaining wall, the sand bedding course shall not be higher than the ground level by 1.2m, the
diameter of the top surface of sand bedding course shall be larger than the diameter 3.0m at
tank bottom, its side slope shall not be less than 1:15, and the side slope shall be protected
with its surface by adopting block stones (Figure 6.2.1).
When the steel oil tank is set on the weak foundation, the loop retaining wall shall be set
around the sand bedding course. The hoop tension resulted by the side thrust shall be
considered in the calculation.
When setting oil tank on weak foundation, the water-filling and prepressing measures
may be adopted against excessive settlement.
72
Figure 6.2.1 Sand Bedding Course of Steel Oil Tank
6.2.2 The oil discharging trestle work should adopt the prefabricated or cast-in-situ concrete
ground, and the oil and water drainage measures shall be considered.
6.2.3 The support of trestle work should adopt prefabricated battened column, plate and
casted-in-site foundation, and the support may adopt open side type expansion joint.
6.2.4 The design of fuel pump room shall consider the explosion protection and pressure relief
requirements, and the reinforced concrete trestlework load-carrying structure should be
adopted. Underground oil pump room shall be separated from the attached ancillary buildings
such as control-room and overhaul room by the settlement joint.
7 Chimney and flue
7.1 General provisions on chimney
7.1.1 The chimney height and the inside diameter at roof hatch shall be supplied by the
technology and should comply with the following series:
Chimney height——80, 100, 120, 150, 1.8, 210, 240, 270, and 300m
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
9 8 7 6
Building name
(I) Main manufacturing building
6 7 8 9
9 9 8 7 Main workshop building 6 7 8 9
9 9 8 7 Electrical integral building 6 7 8 9
9 9 8 7 Boiler cradle (reinforced concrete) 6 7 8 9
9 8 7 6 Blower fan room 6 7 8 9
9 8 7 6 Deashing structures 6 7 8 9
9 8 7 6 Dedusting structures 6 7 8 9
9 9 8 7 Chimney 6 7 8 9
9 9 8 7 Flue 6 7 8 9
9 8 7 6 Indoor coal discharging device 6 7 8 9
9 9 8 7 Coalbreaker chamber and transfer site 6 7 8 9
9 9 8 7 Coal transporting trestle 6 7 8 9
9 8 7 6 Coal transporting tunnel 6 7 8 9
9 8 7 6 Defrosting room 6 7 8 9
9 8 7 6 Integral coal transporting building 6 7 8 9
9 8 7 6 Electronic rail-weighbridge building 6 7 8 9
9 8 7 6 Reinforced concrete silo 6 7 8 9
9 8 7 6 Largespan 6 7 8 9
9 8 7 6 Coal shed
General 6 6 7 8
9 8 7 6 Coal discharging platform in coal depot 6 6 7 8
9 8 7 6 Fuel pump room and fuel store 6 7 8 9
9 9 8 7 Network control building and communication building 6 7 8 9
9 8 7 6 Boiler room for start 6 7 8 9
9 8 7 6 Heavy oil storage and petroleum pump room 6 7 8 9
9 9 8 7 Indoor power distribution unit building 6 7 8 9
9 8 7 6 Outdoor type switchgear rack and support 6 7 8 9
9 8 7 6 Mortar pump room and ash-handling pump room 6 7 8 9
9 8 7 6 Ash settling tank 6 6 7 8
9 8 7 6 Negative-pressure pneumatic deashing structures 6 7 8 9
9 8 7 6 Reverse osmosis apparatus room 6 7 8 9
9 8 7 6 Chemical water treatment room 6 7 8 9
9 8 7 6 Heating buildings (structures) 6 7 8 9
87
Continued
Important power plant General power plant
Local fortification intensity Local fortification intensity
9 8 7 6
Building name
(I) Main manufacturing building
6 7 8 9
9 8 7 6 Internal and external trenches of plant 6 6 7 8
9 8 7 6 Internal and external tunnels of plant 6 7 8 9
9 8 7 6 Steel flue support 6 7 8 9
9 8 7 6 Dewatering bin 6 7 8 9
9 8 7 6 Electro dedusting switchboard room 6 7 8 9
Important power plant General power plant
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
6 Reinforced concrete frame structure
7, 8 Reinforced concrete framework or framework-earthquake resisting wall (antiseismic support)
9 Reinforced concrete framework-earthquake resisting wall (antiseismic support)
9.4.8 The antiseismic support among the lateral columns of main workshop shall comply with
the following requirements:
9.4.8.1 The support of lateral column colonnade shall be determined according to calculation.
The support should be set at the center of stretching section in workshop. When the crane is
available, the column support (above crane beam) shall be set at the both ends in addition.
9.4.8.2 The position of the lower node of lower column support shall assure to be able to
directly transfer the earthquake effect onto the foundation.
9.4.8.3 The length-diameter ratio of the members of intercolumnar bridging should not be
larger than 150.
9.4.8.4 As for the intercrossing antiseismic supports among columns, when the
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length-to-diameter ratio of members is not less than 40 and not larger than 150, the
crosssection of the supporting diagonal rod may be recalculated according to tensile force, but
the unloading influence of pressure bar shall be taken into consideration, the crosssection may
be calculated according to Annex 6 of the "Code for Seismic Design of Building".
9.4.9 The thickness of the longitudinal earthquake resisting wall of mainframe should be
1/30~1/40 of the middle ordinate of columns and shall not be less than 140mm. The
two-direction bifacial reinforcements should be adopted, the total reinforcement ratio at each
direction shall not be less than 0.25%, the diameter of reinforcement shall not be less than
12mm and their corresponding space is 200.
9.4.10 The earthquake resisting wall should be set starting from the foundation base, the wall
body should not be punched, and the hole opening, if it is required to be punched, should not
be larger than 1/6 of the plane area of this layer of wall, and the hole opening should not be
set inclindedly. If it requires inclinded hole opening, the distance from the hole edge to
column edge should not be less than 1/6 of the clear span of wallboard. The bearing capacity
at hole opening shall be determined through calculation. Additional bars shall be set at both
sides and upper part and lower part of the hole opening. The quantity of additional bar may be
1.3 times of the total area of cut steel reinforcement at opening. Slant additional bars must be
set at four corners of the opening at 45°direction, and the steel reinforcement at each nook
should be placed not be less than 500mm2 per 100mm according to the wall thickness.
9.4.11 The precast floor cover of framework shall be set with casted-in-site surface layer
according to the following provisions.
9.4.11.1 When the antiseismic grade is the third or fourth grade and the spacing of columns is
larger than 6m, it shall be set every other layer.
9.4.11.2 When antiseismic grade is the second grade, it shall be set at each layer.
9.4.11.3 The thickness of the casted-in-site surface layer of floor cover should not be less than
50mm, and the mat reinforcement with diameter of 6mm and space of 200mm shall be
arranged.
9.4.11.4 The integrity of precast slabs shall be strengthened and the arris of slab shall be
welded with supporting beam at lower ends.
9.4.12 When the antiseismic grade is the first and second, the antiseismic recalculation shall
be carried out in joint of framework, and recalculation may be omitted when it is the third or
fourth grade, but it shall comply with the structure requirement.
9.4.13 The reinforcements of frame girder style table and joint area shall be adopted with the
following aseismatic measures according to the antiseismic grade.
9.4.13.1 Diameter of hooped reinforcement: it shall not be less than 8mm when the
antiseismic grade is the third grade, not be less than 10mm when it is the second grade, and
not less than 12mm when it is the first grade.
9.4.13.2 The densification scope at beam head should be 1~1.5 times of the beam depth, and
the maximal dandifying length may be 1/3 of clear span.
9.4.13.3 When the antiseismic grade is the second grade or under (or site of I and II types of
degree 8), and the longitudinal construction is set with earthquake resisting wall or
antiseismic support, the columns in the longitudinal joint area of framework may not be set
with dandified hooped reinforcement.
9.4.13.4 The distance among hooped reinforcements in the cryptographic area of beam shall
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not be larger than 250mm when the antiseismic grade is the first or second grades and should
not be larger than 250mm when the antiseismic grade is the third or fourth grade.
9.4.14 The longitudinal reinforcement of column should adopt symmetric reinforcements. As
for the column in the framework-earthquake resisting wall (antiseismic support) system, when
the design experience is available, the space among steel reinforcement direction along long
side distraction of column and the space among the limbs of hooped reinforcements
(including lacing wire) shall not be larger than 350mm, and those along the long side
direction of framework column shall not be larger than 250~300mm.
9.4.15 The endless roof truss or gable wall load bearing scheme of roof beam shall not be
adopted, and separate antiseismic beam (also as windward beam) shall be set. The gable wall
column shall not adopt non-reinforced brick construction. Within the roof truss scope, the
gable wall should adopt light materials and shall be fixed onto roof truss.
9.4.16 The corbel reinforcement for supporting the roof truss and the connected embedded
parts shall comply with the following requirements:
9.4.16.1 The diameter of the hooped reinforcement of corbel shall not be less than 10mm,
their space shall not be larger than 100mm and they shall be placed as the twisted hooped
reinforcement.
9.4.16.2 The length of the anchor bars of longitudinal reinforcements in the steel plate at
corbel top surface should be la+50mm (la is the anchoring length of tensile reinforcement);
the weld strength of anchor bar shall be larger than its strength.
9.4.16.3 The longitudinal reinforcements (longitudinal reinforcements bearing tensile force of
horizontal earthquake effect) welded with the top surface steel plate of corbel shall be not less
than two sticks and its diameter shall not be less than 12mm when it is degree 6 or 7; not less
than two sticks and the diameter shall not be less than 14mm when it is of degree 8; and not
less than two sticks and the diameter not less than 16mm when it is of degree 9.
9.4.17 The elements of the roof without purline shall comply with the following requirements:
9.4.17.1 In the site of Class III and Ⅳ of degree 7, the large-scale roof panels in the first row
at both ends of different roof truss shall ensure the four corners are welded with welding seam,
other roof panels shall be with at least three corners being welded with welding seam.
9.4.17.2 As for the roof panel in the first row at both sides when it is degree 7 and when it is
degree 8 and 9, the length of the attachment weld between roof panel and roof truss shall not
be less than 80mm, and the weld bead height shall not be less than 6mm.
9.4.17.3 When it is of degree 8, the roof cover of scuttle should adopt light plates. When the
roof cover adopting large-scale roof panels of degree 7, in the first bay at both ends of the
workshop unit (in all the bays when it is of degree 8 or 9), the hooks of large-scale roof panel
shall be buried near to the ends, and the adjacent hooks shall be welded with bar dowel in
longitudinal direction and transverse direction. When the roof panel is not set with hooks,
embedded parts shall be set at top surface of the four corners on roof panel and the adjacent
embedded parts shall be welded with bar dowel.
9.4.17.4 When it is of or above degree 7, full-length inter-tie shall be set at the top chord and
bottom chord at head ends of roof truss that is with span of roof truss equal to or larger than
18m, and the inter-tie shall be considered as compressed bar.
9.4.17.5 The ring beam shall be firmly connected with column or roof truss. The quantity of
ring beams at column top and the quantity of anchor bars used for column connection shall
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not be smaller than 4, the diameter shall not be less than 12mm, and the length inserting into
concrete column shall not be less than the anchoring length of tensile reinforcement.
9.4.17.6 The plane dimension of concealed parts at top chord of roof truss that is welded with
roof panel should not be less than 200mm×200mm, the quantity of the bent bars of the
embedded plate at top chord ends should not be smaller than 4, and the diameter of bent bar
shall not be less than 12mm.
9.4.18 The length-diameter ratio for the members in roof supporting (including scuttle
supporting) should comply with the following requirements:
Length-diameter ratio of pressure barλ≤200
Length-diameter ratio of drawbarλ≤300 when it is of degree 6 and 7
λ≤250 when it is of degree 8 or 9
9.4.19 Generally, the reinforced concrete precast slabs may be adopted. And light steel plate
such as profile steel plate may be adopted if the main workshop is with proper conditions. The
light roof should be adopted when it is degree 9.
9.4.20 In order to strengthening the longitudinal rigidity at head end of roof, the scuttle at
both ends or one end of the workshop unit may be set starting from the second
intercolumniation at head end. The side plate at both ends of monitor frame and the upright
column of monitor frame should adopt the bolted connection. When it is of degree 8 and 9,
one lateral bracing at the top chord of roof truss shall be set at both ends of the punching
scope of scuttle in addition partially.
9.4.21 Shoring layout of the machine hall cover shall comply with relevant requirements of
"Code for Seismic Design of Buildings"; when transverse box and bent system structure are
present, it shall also meet the following requirements:
9.4.21.1 When the seismic grade is 8°and 9°, the last quarter of roof truss with span of no less
than 24m shall be set with closed horizontal shoring. When the through roof truss adopts
light-duty roof cover, the first quarter shall be set with closed horizontal shoring.
9.4.21.2 When the seismic grade is 8° and 9°, a beam of vertical bracing along full length
shall be set in the center of the trapezia and arched roof truss around every other 12m. When
scuttle is available, it may be set in harmony with the vertical bracing of the scuttle heel post.
When the height of the roof truss end is no less than 900mm, vertical bracing along full length
shall be set on both ends of the roof truss respectively.
9.4.22 Stipulation on boiler cradle is applicable to aseismic design of reinforced concrete and
pendant boiler truss with composite structure possessed of shaking point or set with guiding
mechanism.
9.4.23 When the boiler cradle and roof requires sealing, light-duty steel plate should be
adopted.
9.4.24 The boiler cradle may generally calculate horizontal earthquake effect in the two
principal axes directions, and make aseismic checking. Horizontal earthquake effect in
directions shall be assumed by the side force resistant members in that direction.
9.4.25 When calculating the earthquake effect for the boiler cradle, all of the boiler cradles
supporting the furnace shaft should be connected as an integral part, and major connected
nodes shall consider impact of earthquake effect vertically and horizontally respectively.
When calculating the earthquake effect of the boiler cradle with response spectrum modal
decomposition method, at least vibration modes should be considered.
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9.4.26 When the earthquake effect is calculated for the boiler cradle, the gravity rigidity and
boiler cradle joint work composed of suspended furnace shaft and steeve, and its gravity
rigidity may be calculated by formula (9.4.26).
knl
EI
l
GK
30
6 (9.4.26)
Where
K0——Gravity rigidity (kN/m);
l——Steeve length (m);
G——Gravity loading of suspended furnace shaft (kN);
E——Elastic modulus of the steeve (kN/m2);
I——Inertia moment of the steeve (m4);
n——Total steeve number;
k——Rigidity regulation factor, it is generally 1.5~2.0.
9.4.27 Partial earthquake effect of the boiler cradle shall be calculated by the multi-mass
system; mass of the boiler cradle are focusing on floors separately, the mass of the furnace
shaft is calculated by the gravity rigidity-based spring, and its mechanical model sees Figure
9.4.27.
9.4.28 When calculating the earthquake effect of furnace shaft itself according to Figure
9.4.27, its seismic influence factor shall not be less than 0.2amax.
9.4.29 The normal value of earthquake effect for the suspended furnace shaft shall be
provided by the manufactory. The calculation diagram of the suspended boiler cradle and
furnace shaft sees Figure 9.4.29. When data is lacking, it is simplified calculation, and
earthquake effect caused by the suspended furnace shaft may be calculated according to the
following formula:
Figure 9.4.27 Schema of Boiler Cradle Mechanical Model
BSs GaF 111 (9.4.29)
Where:
F11——Earthquake effect caused by the suspended furnace shaft (kN), the whole value
acts on the column top of the boiler cradle;
ξs——Regulation factor of the modal contribution, ξs=1.2;
a1——Horizontal seismic influence factor correspondent with the fundamental period of
the furnace shaft, and the fundamental period of the furnace shaft may be 1.5s;
BSG ——Total gravity load of the suspended furnace shaft
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Factor a is the product of regulation factor of modal contribution ξs and the horizontal
seismic influence factor a1 (namely a=ξsa1), it may be adopted according to Table 9.4.29-1
and Table 9.4.29-2.
9.4.30 When the aseismic strength is 6°, the aseismic strength may not be checked for the
boiler cradle, but requirement of anti-seismic construction measures shall be met.
Figure 9.4.29 Calculation Diagram of Suspended Boiler Cradle and Furnace Shaft
Table 9.4.29-1 Seismic Coefficient a of Near Earthquake Effect
Strength
Site types 6 7 8
Ⅰ 0.008 0.016 0.032
Ⅱ 0.012 0.023 0.046
Ⅲ 0.015 0.029 —
Ⅳ 0.023 0.045 —
Note: — in the table refers to reinforced concrete structure adopted in that condition, but it has many difficulties from the
aseismic design angle, so it is not recommended any more.
Table 9.4.29-2 Seismic Coefficient a of Distant Earthquake Effect
Strength
Site types 6 7 8
Ⅰ 0.010 0.019 0.038
Ⅱ 0.015 0.029 0.058
Ⅲ 0.020 0.039 —
Ⅳ 0.029 0.058 —
9.4.31 Earthquake effect of columns (or frames) of the boiler cradle may be distributed by the
rigidity proportion of the members. The distribution ratio of the intermediate truss with
smaller rigidity should not be less than 10%.
9.4.32 The normal value of the earthquake effect for the boiler cradle may be calculated by
the following formula:
22lj SSS (9.4.32)
Where
Sj——Normal value of the earthquake effect for the boiler cradle;
Sl——Normal value of the earthquake effect caused by furnace shaft on the column top
9.4.33 When the compartment between the furnace shaft and boiler cradle is set with
horizontal elastic copulation shaking points or guiding mechanism members in places, the
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calculation for the earthquake effect of the boiler cradle should be made according to plane
multi-mass system and with response spectrum vibration mode analytical method. Its
calculation diagram sees Figure 9.4.33.
Figure 9.4.33 Calculation Diagram of Suspended Boiler Cradle
9.4.34 Aseismic design of the boiler cradle shall consider reducing the eccentricity of the
rigidity center and mass center of the boiler cradle. When the eccentricity is large, torsion
impaction shall be considered.
9.4.35 The joint between the large plate beam and column top of the reinforced concrete
boiler cradle, or between the steel column foot and the foundation shall be multiplied by
additional coefficient 1.5 when calculating the earthquake effect. Check the earthquake effect
of the roof structure: when simplified method is adopted to calculate the earthquake effect, its
normal value should be triangularly distributed, and the calculated amount should be
multiplied by augmenting factor 3.
9.4.36 After setting shaking device for the suspended furnace in the seismic area, local
bearing capacity of corresponding load-bearing member shall be checked and it shall comply
with the following relevant requirements:
9.4.36.1 The rigidity of the shaking device should be within 10~20kN/mm, and the force
transferring size is determined by calculation.
9.4.36.2 Free expansion that can comply with the boiler body
9.4.36.3 The stress is definite, but it cannot transfer detonation pressure of the hearth and
vibration when being burnt.
9.4.37 Aseismic structure measures of the reinforced concrete boiler cradle may comply with
Table 9.1.5. When the aseismic grade is the first grade, assembled monolithic reinforced
concrete structure may be adopted under the conditions with reliable measures and design
experience.
9.5 Master control building and distribution equipment building
9.5.1 The Master control building and distribution equipment building may select its
structural shape according to the site soil type and fortification intensity on the basis of Table
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9.5.1. Table 9.5.1 The Structural Shape of Master Control Building and Distribution Equipment Building
Fortification intensity Site type Structural shape
6 ~Ⅰ Ⅳ Masonry structure*
and Ⅰ Ⅱ Masonry structure*
7
~Ⅲ Ⅳ Masonry structure * and frame structure
and Ⅰ Ⅱ Masonry structure * and frame structure
8
and Ⅲ Ⅳ Frame structure
9 ~Ⅰ Ⅳ Frame structure
Note: 1 Masonry structures listed in this table are all set with reinforce concrete tie column and collar tie beam;
2 Frame structure listed in the table is cast-in-situ reinforced concrete frame structure.
* refers to master control building with voltage of 220kV or below and distribution
equipment building with voltage of 110kV or below. Frame structure should be adopted for
the master control with voltage of 220kV or above and distribution equipment building with
voltage of 110kV or above;
9.5.2 The minimum section of the reinforced tie column is 240mm×240mm, the longitudinal
reinforcement should not be less than 4 and the diameter shall not be less than 12mm; the
stirrup diameter should be 6mm and corresponding interval should be 200mm. Tie-bar of the
walling shall dive into the tie column. stirrup in the up-and-down ends of various layers of
columns should be crowded properly. The reinforcing bars of the tie column on the open layer
shall be determined by calculation.
9.5.3 Shelving length of reinforced concrete floor or roof panel diving into the wall shall be
no less than 120mm, and its shelving length on the beam shall be no less than 80mm. The side
of the prefabricated panel near the external wall shall be knot drawn together with the ring
beam.
For the roof cover of bayed floor slab, or building with aseismic strength of 7°, 8° and 9°,
when the ring beam is set on the base plate, joint between plates, plate and beam, or between
tie column and ring beam shall be strengthened.
9.5.4 The ring beam shall be sealed. The top level of ring beam should be identical to that of
the prefabricated panel, and the ring beam should be set close to the panel. The
cross-sectional width of the ring beam is same as the wall thickness and its height should not
be less than 180mm. The ring beam should be cast-in-situ. The top of the bricking-up
partition shall be provided with reinforced concrete capping beam. The ring beam on the
unsealed walling top shall be increased with horizontal rigidity, and its section and reinforcing
bars are determined by calculation.
9.5.5 The stud in the interlayer of the master control building shall be reinforced concrete
column.
9.5.6 The aseismic design of the correspondence building may comply with relevant
regulations of this Section.
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9.6 Coal-shifting trestle
9.6.1 The interval between the trestle and the adjacent buildings shall be set with
earthquake-proof joint. The earthquake-proof joint shall comply with the following
requirements:
9.6.1.1 The earthquake-proof joint may comply with relevant regulations of "Code for
Seismic Design of Buildings". For general trestle, when the aseismic strength is 7, 8 or 9°, its
width should not be less than 70mm, 90mm and 120mm respectively.
9.6.1.2 When earthquake-proof joint is set in the middle of the trestle, support shall be set on
both sides of the joint.
9.6.1.3 When the aseismic strength is 9°, the joint should be two-way deflection
earthquake-proof joint.
9.6.2 When the aseismic strength is 7 or 8°, sliding support shelved on the adjacent buildings
may be adopted to ensure the longitudinal deflection (the coal-shifting trestle leading to the
main building may be set with suspended bearing, sliding support or roller support on its top).
The bearing hereof shall be able to transfer horizontal earthquake effect along the transverse
direction of the structure.
9.6.3 Rigidity of the adjacent transverse frame structures of the trestle should be close to each
other as far as possible. When making the transverse aseismic calculation for the coal-shifting
trestle, integral work of the horizontal structures of the trestle should be considered, and
elastically supported beam structure with different types may be adopted for the calculation
(Annex H). When l/B is no greater than 8 (l is the total trestle length and B is the deck width),
it is rigid deck; when l/B is greater than 8, it is elastic deck.
When the coal-shifting trestle has difficulties in calculating earthquake resistance as an
integral part, weight above the deck may also be distributed to the horizontal structure
according to lever principle, and horizontal structure is calculated separately. Aseismic
bearing capacity of general high-class horizontal structure shall be improved properly.
9.6.4 When the trestle is truss, portal rigid frame shall be set on its both ends. The first quarter
and last quarter of the truss should be set with horizon crossing support along full length.
9.7 Silo
9.7.1 The structural arrangement of the silo shall strive to be simple and regular, and its mass
and rigidity is distributed evenly and symmetrically along the two principal axes directions.
9.7.2 The silo should be disconnected to the adjacent trestle, so that to form independent
structural unit. When the silo is used as supporting structure of the trestle, flexible joint shall
be adopted (such as ball seat and steeve).
9.7.3 The silo should adopt monolithic reinforced concrete structure.
9.7.4 The high-capacity silo in the power plant should adopt tunnel wall supported tower silo,
and shall reduce the punch size of the support ring wall. When arc battened wall is formed by
the setting of large hole, the section of the battened wall shall be equal or similar.
9.7.5 Load-carrying member of the structure on the silo should adopt reinforced concrete
frame or steel frame.
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9.7.6 Roofing of the building on the silo should adopt light roofing or cast-in-situ reinforced
concrete roofing. When the aseismic strength is 8° or below, precast reinforced concrete
roofing may be adopted.
9.7.7 The enclosure walling of the building on the silo may adopt brickwork when it locates
in I or II-type site with aseismic strength of 6, 7 or 8°. When the aseismic strength is above 9°,
building on the silo shall adopt light materials.
9.7.8 When calculating the horizontal earthquake effect of the cylinder silo structural unit, the
effective gravity loading of the bin stock shall be multiplied by the reduction coefficient. For
the cylinder silo, the reduction coefficient is 0.8.
9.7.9 The earthquake effect of the tunnel wall and underpart supporting structure of the
cylinder silo may be distributed according to their relative stiffness respectively. For the
design value of the bending moment on both ends of the support column, it shall be multiplied
by augmenting factor 1.5. The stirrup within up-and-down 1.5 times the long side of the
column section of the support column node shall be crowded.
9.7.10 The maximum axle load ratio of the silo column should meet the following
requirements:
9.7.10.1 General support column: when the strength is 6 or 7°, it is no greater than 0.75; when
it is 8°, it is no greater than 0.7; when it is 9°, it is no greater than 0.65.
9.7.10.2 When the support column id deployed with screw compound stirrup, it is 0.75.
9.7.11 The thickness of the reinforced concrete tower silo wall shall not be less than 180mm
when the strength is 6 or 7°, and it shall not be less than 200mm when the strength is 8 or 9°.
The tunnel wall shall adopt double-layer two-way reinforcement, and the total reinforcement
ratio of vertical or circumferential horizontal reinforcement should neither be less than 0.4%.
The interval between the double-layer steel bar shall be set with tie-bar: when the aseismic
strength is 6 or 7°, the diameter is 6mm and the interval is 700mm; when the aseismic
strength is 8 or 9°, its diameter is 6mm and its interval is 500mm.
When the tunnel wall is set with hole, the holes should be arranged evenly and
symmetrically; the corresponding central angle of the hole shall not be greater than 70°, and
the total punching central angle in the same horizontal cross-section shall not be greater than
140°. When the side length of the opening mouth is less than 1m, sides of the opening shall be
set with at least two additional bars in diameter of 20mm according to Figure 9.7.11. The
sectional area of the additional bar hereof is no less than 1.3 times of the cut off reinforcement
area at the opening. The inside and outside layer of the four corners of the opening are all
deployed with a stick of diagonal reinforcement in diameter of no less than 20mm. When the
opening is large, opening deep frame shall be set, and the reinforcing bars of the deep frame
should not be less than 1.3 times of the cut off reinforcement area at the opening.
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Figure 9.7.11 Reinforcement of Wall at the Opening
9.7.12 When the building on the silo is brickwork, the following structural requirements shall
be met:
9.7.12.1 The interval of reinforced concrete tie columns should not be greater than 4m.
9.7.12.2 The interval between ring beams should not be greater than 3.5m and one beam of
ring beam shall be set on the wall roof.
9.7.12.3 The prefabricated panel joint corresponding with the tie column shall be set with
cast-in-situ reinforced concrete caulked joint belt which is protruding off the steel bar and
anchoring into the tie column.
9.8 Equipment foundation
9.8.1 The aseismic checking of the equipment foundation shall generally check the strength of
the structure itself, and the overturning shall also be checked if necessary.
9.8.2 When calculating the earthquake effect of the equipment foundation, the equipment and
the foundation should be deemed as an integral to determine the structural calculation
diagram (Figure 9.8.2); impaction of connections among equipments may not be considered.
9.8.3 The combination of earthquake effect and other loads effect may refer to Section 9.3 of
this Stipulation, and it should also comply with the following requirements:
Figure 9.8.2 Aseismic Checking Diagram of the Equipment Foundation
105
(a) Practical schema; (b) Calculation diagram
Dead load (including gravity load of the equipment)
Design dynamic load of the equipment, its combination coefficient is 0.25.
Incidental dynamic load and installation repair load may not be considered.
9.8.4 When the aseismic strength is 7° or above, the equipment foundation (including the
passable platform) shall not be consolidated with the adjacent buildings. The walkway plate
shall be provided with adequate support length and slip interval.
9.8.5 The supporting structure and foundation of the water film duster shall not adopt
masonry structure.
9.9 Pipeline support
9.9.1 This Section is applicable to independent type support without longitudinal member
connection between brackets and with the pipeline directly laying on the support.
9.9.2 The pipeline support adopts reinforced concrete structure. When the aseismic strength is
8° or above, intermediate support should not adopt half swing joint type.
9.9.3 When the aseismic strength is 6°, the aseismic strength may not be checked, but the
requirement of anti-seismic construction measures shall be met. When the aseismic strength is
8 or 9°, the pipeline support may make aseismic checking and take structural measures
according to the fortification intensity.
9.9.4 The computing unit and calculation diagram of the pipeline support may be selected
according to the following principles:
9.9.4.1 The length (l) of the longitudinal computing unit is the center-to-center distance of the
compensator.
9.9.4.2 The length (l) of the transverse computing unit is the center-to-center distance around
the supports.
Structural calculation diagram in the computing unit may be considered by single mass
point for the monolayer pipeline support, see Figure 9.9.4-2.
Figure 9.9.4-1 Calculation Diagram of Independent Type Support
106
Figure 9.9.4-2 Calculation Diagram of Single Mass point
When the pipes are multilayer, it may be simplified to corresponding multi-mass system
according to the pipeline laying positions.
9.9.5 The combination of the effective gravity loading and loads effect of the support shall be
valued according to requirements of this Article.
9.9.5.1 The gravity load includes the following items:
(1) Pipeline gravity, including pipeline, inner lining, insulating layer and deadweight of
the pipeline accessory;
(2) Medium gravity in the pipeline, it is the gravity under normal operation (provided by
the process);
(3) Gravity load of the pipeline support: when it is single-mass-system, the computation
period is 1/4 of the gross weight, and the earthquake effect calculation tales 2/3 of the gross
weight.
(4) Sleet load, it is 50% for cold pipeline.
9.9.5.2 The earthquake effect shall be combined with the following loads effect:
(1) Dead load, including the dead weight of the equipment.
(2) Sleet load, it is 50% for cold pipeline;
(3) Horizontal thrust caused by the thermal expansion of the pipeline during normal
operation;
(4) Wind load, it is valued according to requirements of "Code for Seismic Design of
Buildings".
9.9.6 Longitudinal earthquake effect calculation of the pipeline support: intermediate support
and fixed support earthquake effect may be distributed according to the lateral flowing
rigidity of the support, when the earthquake effect of the intermediate support is greater than
the friction of the pipeline, frictional impact may be reduced.
9.9.7 When the seismic strength is 8 or 9° and one of the following conditions are met,
vertical earthquake effect shall be considered:
9.9.7.1 The combined type support with span of greater than 24m (the pipeline is used as truss
member)
9.9.7.2 For T-shape orⅡ-shape support with overhung outrigger, when their outrigger is set
with large-diameter pipeline;
9.9.8 The beam and column of the pipeline support shall be prefabricated integrally, and the
beam column node shall meet the structure requirement of the frame node.
9.9.9 The support or suspension measures on the pipeline support shall be reliable, and the
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side pipeline on the top layer beam shall be set with measures preventing pipeline shattering.
108
Annex A Calculation Diagram of Transverse Frame (Bent Frame)
A1.0.1 Simplified calculation for frame (bent frame) of the main building sees Figure A1.
Figure A1 Simplified Calculation Diagram of Transverse Frame (bent Work)
(a) External coal silos type; (b) Internal coal silos type (single frame); (c) Internal coal silos type (double frame); (d) Suspended
boiler independent type
109
Annex B Vertical And Horizontal Calculation Diagram of Suspended
Boiler Framework
B1.0.1 The vertical and horizontal calculation diagram of suspended boiler framework sees
Figure B1.
Figure B1 Vertical and Horizontal Calculation Diagram of Suspended Boiler Framework
(a) single-column multilayer transverse framework; (b) single-column monolayer transverse framework; (c) battened column
multilayer transverse framework; (d) battened column multilayer transverse framework; (e) s framework-type transverse
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,
ZHU Daojiang, QIU Huixian, ZHUANG Wenfu, HE Ruomei, QIAN Yongrui, JIAN Guoping,
HUANG Yingbo, YAN Shanzhang, ZHANG Fangqi, LI Bingyi, DING Jialiang, LIU
Maosheng, SONG Jingyang and WEN Liangmo
