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National Standard of the People9s Republic of China '1

P

Code for Design of Steel Structures 1 GBJ 17-88

l-G87/3--&$?;:.- #f+$?E ,:-* qq-.<i)t

July 1,1989 BeiJing

National Standard of the People9s Republic of China Code for Design of Steel Structures

GBJ 17-88

Chief editing organization :

Ministry of Metallurgical Industry

People9s Republic of China

Approving organization :

Ministry of Construction

People9s Republic of China

Date of enforcement :

July 1,1989

CONTENTS

General

Materials

Basic design requirements

3. 1 Design principles

3. 2 Design indices

3. 3 Requirements for deformation of structures

Calculation of flexural members

4. 1 Strength

4. 2 Overall stability

4. 3 Local stability

Calculation of axially loaded members and members subjected

to combined axial load and bending

5. 1 Axially loaded members

5. 2 Members subjected to combined axial load and bending

5. 3 Effective length and allowable slenderness ratio

5. 4 Local stability of compression members

Fatigue calculation

6. 1 General requirements

6. 2 Fatigure calculation

Calculation of connections

7. 1 Welded connections

7. 2 Bolted and riveted connections

7. 3 Flange connection of built-up I- girders

7. 4 Supports

Requirements for detailing

8. 1 General requirements

8. 2 Welded connections

8. 3 Bolted and riveted connections

8. 4 Structural members

8. 5 Requirements for crane girders and crane trusses (or - I -

similar girders and trusses)

8. 6 Fabrication, transportation and erection

8. 7 Corrosion protection and heat isolation

9. Plastic design

9. 1 General requirements

9. 2 Calculation of members

9. 3 Allowable slenderness ratio and detailing requirements

10. Steel tubular structures

1 1. Light steel structures of round bars and small angles

12. Composite steel and concrete beams

12. 1 General requirements

12. 2 Calculation of sections and shear connectors

12. 3 Requirements for detailing

Appendix 1 Overall stability factor of beams

Appendix 2 Calculation of local stability of girder web

Appendix 3 Stability factor of axially loaded compression

members

Appendix 4 Effective length factor for columns

Appendix 5 Classification of members and connections for

fatigue calculation

Appendix 6 Effective area of bolts

Appendix 7 Conversion factor between legal and non-legal units

of weights and measures

Appendix 8 Explanation of words in this Code

MAIN SYMBOLS

Actions and effects of actions .+- F - concentrated load ;

M - bending moment; - N - axial force;

P - pretension of high-strength bolts ;

V - shear force ;

R - reaction of supports.

Calculation indices

E - modulus of elasticity of steel ;

E, - modulus of elasticity of concrete ;

G - shear modulus of steel;

NE - Euler' s critical force ;

N: - design value of tensile capacity of an anchor bolt ;

N! , N! , N,b - design value of tensile, shear and bearing

capacity of a bolt;

N: , N: , Wc - design value of tensile, shear and bearing

capacity of a rivet ;

N: - design value of shear capacity of a connector ;

NPj , Nij - design value of tensile and compressive capacity

of sub- pipe at a joint ;

f - design value of tensile, compressive and bending strength

of steel ;

f, - design value of shear strength of steel;

f,, - design value of end bearing strength of steel ;

f,, - design value of tensile strength of reinforcing bars ;

f, - yield strength ( or yield point )of steel ;

f:- design value of tensile strength of anchor bolts;

f: , f! , f,b - design value of tensile, shear and bearing

strength of bolts; - lu -

f: ,f: , fE - design value of tensile, shear and bearing

strength of rivets ;

fy , fy , f," - design value of tensile, shear and compressive

strength of butt welds ;

r: fy - design value of tensile, shear and compressive strength

of fillet welds; - fee - design value of axial compressive strength of concrete ;

f,- design value of bending strength in compression zone

of concrete ;

o- normal stress ;

o, - , local compressive stress ;

of-- stress normal to the direction of the length of a fillet weld,

calculated on its effective section;

A a - stress range for fatigue calculation;

he-- equivalent or reduced stress range for variable amplitude

fatigue ;

[ ~ o ] - allowable stress range for fatigue;

om, cr,,, , t, - critical stress of plate under individual action of

bending stress, local compressive stress and shear stress ;

t - sheat stress;

tf- shear stress of a fillet weld a10,ng the direction of its

length ;

p - density of mass.

Geometric parameters

A - gross sectional area ;

A, - net sectional area ;

H - column height;

HI , HP , H3 - height of the upper, middle ( or lower ) , and lower

portion of stepped columns, respectively ;

I - moment of inertia of gross section;

I, - moment of inertia of net section ; - w -

S - static moment of gross section ;

W - gross section modulus ;

Wn - net section modulus ;

W, - gross plastic section modulus ; -I

W,, - net plastic section modulus ;

a - spacing; - b - plate width or free outstand of plate;

b, - flange width between webs of a box-section ;

upper width of concrete slab haunch;

b, - outstand of stiffeners;

d - diameter;

de - effective diameter ;

do - hole diameter ;

h - full height of a section (section depth) ;

hcl - thickness of concrete slab ; hc2 - thickness of concrete haunch ;

he - effective thickness of fillet welds ;

hf -- leg size of fillet welds ; . h,- web height (web depth) ;

- ho - effective web height ;

i - radius of gyration of a section;

1 - length or span length;

L - effective length ;

1, - effective length of welds ;

1,- assumed distribution length of a concentrated load on

the edge of effective web height;

t - plate thickness ; wall thickness of main pipes ;

t, - wall thickness of sub - pipes ; stiffener thickness ;

t, - web thickness ;

u - angle ;

8 - angle;

h - slenderness ratio ;

ho - equivalent slenderness ratio.

Coefficients of calculation and others

C - dimensional parameter for fatigue calculation ;

C1 , Cz - dimensional parameter for checking girder web buckling ; 2

K1 , Kz - ratio of linear stiffness of members ;

- kl , kz , k3, k4 - dimensional parameters for calculation of

stiffener spacing of girder webs;

n - number of bolts, rivets or connectors;

number of stress cycles ;

nl- number of high-strength bolts on a calculated section;

nf- number of force -transfer friction surfaces in a high-

strength bolted connection ;

n,- number of shear planes of bolts or rivets;

a - coefficient of linear expansion ;

a, - modular ratio of steel to concrete;

elf- equivalent factor of underloading effect for fatigue -

calculation ;

a. - stress gradient factor of column web ;

al - factor for planed and closely fitted web edge;

fl - diameter ratio of sub-pipe to main pipe;

parameter for fatigue calculation ;

(3b - factor of eqivalent moment for overall stability of beams ;

Pf- enlargement coefficient for design value of the transverse

fillet weld strength ;

& , a - factor of equivalent moment for beam- column stability ;

fll - enlargement coefficient of design value of strength for

reduced stress ;

y - plasticity adaptation factor;

- parameter for checking beam overall stability;

T - factor taking account of the effect of bending stress

on buckling of girder webs;

T ~ - factor of unsyrnrnetry of a beam section ;

,TZ - parameters for calculation of the effective length of - M -

stepped columns ;

IJ. - slip coefficient for faying surfaces in a high-strength

bolted connection ;

effective length factor of columns;

p1 , p2 ,113 - effective length factor of the upper, middle (or

lower) and lower portion of stepped columns;

c1 - aspect ratio of the compression subpanel of girder web ;

cp - stability factor of axially loaded compression members ;

G, cpb - overall stability factor of beams ;

Y - enlargement coefficient of a concentrated load;

Y,, , Ya, Yd- parameter for capacity calculation of directly

welded pipe joints.

1. GENERAL

1. 0. 1 This Code intends to implement the technical-economic policy of the

State in the design of steel structures, by using advanced technology and en- .,

suring economy, reasonableness, safety, suitability for use and good quality

- of the strutures.

1. 0. 2 This Code applies to the design of steel structures of industrial and civil

buildings and allied engineering structures.

1. 0. 3 The design principles of this Code are based on the NUnified standard

of Building Structure DesignN (GBJ68 - 8 4).

1. 0. 4 In designing steel structures,designers shall consider the real situation

of the project, select reasonably the material, the structural scheme and de-

tailing measures, and shall fulfil the requirements of strength, stability and

stiffness of the structure during transportation ,erection and service. Typical

and standardized structures and structural members should be adoped in pref-

erence, the amount of fabrication and erection work should be reduced, fire

protection requirements should be met and due attention should be paid to

corrosion resistance of the structures.

1. 0. 5 On the design drawings of steel structures and the steel material order-

ing documents, shall be indicated the steel grade (for common carbon steel,

the kind of stee1,furnace type,degree of deoxidization etc. shall also be in-

cluded ) , the kind (or grade) of connection materials, and the additional

items of guarantee for mechanical properties and chemical composition of the

steel. Moreover, the required class of weld quality shall also be indicated on

the design drawings of steel structures (the inspection criteria of the weld

quality shall conform to the current national standard, "Code for Construc-

tion and Acceptance of Steel StructuresI1 ) .

1. 0. 6 The design of steel structures with special requirements and those un-

der special circumstances shall furthermore comply with the relevant current

national codes.

2. MATERIALS

2. 0. 1. The grade and quality of steel used for load -carrying struc-

tures shall be selected according to the importance, the loading char-

acteristic, the connection device and the working temperature of the

structure, etc. . The material of load- carrying structures may be grade 3 (rimmed

or killed) steel of open - hearth or oxygen - converter production,

16Mn steel, 16Mnq steel, 15MnV steel or 15MnVq steel. Their I

quality shall conform respectively to the requirements of the current

standards It Technical Requirements for Carbon Structural Steel" , It Technical Requirements for Low - alloy structural Steel" and

It Technical Requirements for Carbon - and Low - alloy Steel Plate ,-

for Bridges" .

2. 0. 2. Grade 3 rimmed steel should not be used for the following

load - carrying structures :

1. Welded structures : crane girders and crane trusses for heavy duty

cranes or similar structures, crane girder and crane trusses for light

and medium duty cranes or similar structures whose calculation tem-

perature in winter is equal to or less thqn T- 2 0 "C , and other load -

carrying structures whose calculation temperature in winter is equal

to or less than -30°C.

2. Non - welded structures: crane girders and crane trusses for

heavy duty cranes or similar structures, whose calculation tempera-

ture in winter is equal to or less than - 2 0 "C . Note: The calculation temperature shall be determined by the out- door calculation temperature for winter air - conditioning specified in

the currrent national standard, Code for Design of Heating, Venti-

lation and Air - conditioningtt. For structure inside a building with - 3 -

heating, the specified value may be increased by 10°C. d

2. 0. 3. Steel for load - carrying structures shall be guaranteed for

meeting the requirements of tensile strength, elongation, yield

stength ( or yieled point) and also of proper sulfur and phosphorus

contents. For welded structures, the steel shall also be guaranteed

for proper carbon content. If necessary, the steel for load-carrying

structures shall also be guaranteed for passing the cold - bending

test. Steel used for welded crane girders and crane trusses for heavy

duty cranes or medium duty cranes with capacity equal to or larger

than 50t or similar structures shall be guaranteed for meeting the re-

quirement of notch toughness at normal temperature, But, in case

the winter calculation temperature is equal to or lower than - 2 0 "C , the grade 3 steel shall also be guaranteed for meeting the requirement

of notch toughness at the temperature - 2o0C, whereas the steels

I 6Mn, 1 6Mnq ,15MnV and 15MnVq shall be guaranteed for meeting

the requirement of notch toughness at the tempreture of - 40 'C.

The steel used for non-welded crane girders and crane trusses for

heavy duty cranes or similar structures shall also be guaranteed for

notch toughness if necessary.

2. 0. 4 For cast steel parts, steel grades ZG2 00 - 4 00 , ZG2 3 0 - 450, ZG270-500 or ZG310-570 specified in the current stan-

dard, Cast Carbon Steel for General Engineering UseN , shall be

used.

2. 0. 5 The connection material of steel structures shall comply with

the following requirements : ~ I. The electrodes used for manual welding shall meet the require- I

ments of the current standard, Carbon Steel Coated Electrodes1' or - 4 -

Low-alloy Steel Coated ElectrodesN. The type of selected electrodes

shall match the base metal in strength. For crane girders and crane

trusses for heavy duty cranes or similar structures, low - hydrogen

electrodes should be used.

2. The wire and flux used for automatic or semi-automatic welding

shall match the base metal in strength. Wires shall meet the require-

ments of the current standard, " Wire Used for WeldingN.

3. Ordinary bolts may be made of grade 3 steel specified in the cur-

rent standard, Technical Requirements for Carbon Structural

SteelN . 4. High strength bolts shall meet the requirements of the current

standard, Type, Dimention and Technical Requirements for High

Strength Bolts with Large Hexagon Heads, Large Hexagon Nuts and

Washers for Steel StructuresN or Type, Dimension and Technical

requirements for Shear Type High Strength Bolt Sets for Steel Struc-

tures".

5. Rivets shall be made of ML2 or ML3 steel specified in the current

standard, If Technical Requirements for Hot - rolled Round Bars of

Carbon Steel for Rivets and Boltsrr.

6. Anchor bolts may be made of grade 3 steel or 16Mn steel speci-

fied respectively in the current standard, rr Technical Requirements

for Carbon Structure SteelN or Technical Requirements for Low-

alloy Structural Steelrt.

BASIC DESIGN REQUIREMENTS

3 . 1. Design Principles

3. 1. 1 Except for fatigue calculation, for all calculations the limit state de-

sign method based on probabilistic theory is adoped, using design expressions

with partial safety factors.

3. 1. 2 The limit states of structures are those states critical for a structure or

structural member to meet requirements for fulfiling a certain specified func-

tion, beyond which the structure or stuctural member ceases to satisfy the de-

sign requirements.

Load - carrying structures shall be designed according to the following ulti-

mate limit states and normal serviceability limit states:

1. The ultimate limit states are those associated with the attainment of maxi-

mum capacity of a structure or structural member or of deformation no

longer suitable for carrying load.

2. The serviceability limit states are those associated with the attainment of -- - certain specified limiting value for normal use of a structure or structural

member.

3. 1. 3 In the design of steel structures, different classes of safety shall be

adoped according to the consequence of damage which may be caused by a

structural failure.

Steel structures of industrial and civil building may be taken as safety class 2 whereas for a special building structure the safety class should be dealt with

individually in conformity to its actual condition.

3. 1. 4 In designing a steel structure according to the ultimate limit state, ba-

sic combination of load effects shall be considered and, if necessary, the ac-

cidental combination of load effects shall also be considered.

In designing a steel structure according to serviceability limit state, only the - 6 -

combination of short term load effects shall be considered, but with the ex-

ception of composite steel and concrete beams.

d 3. 1. 5 In checking the strength and stability of structures or structural mem-

bers and also the strength of connections, the. design value of loadings shall be

- used (i. e. the characteristic value of loading multiplied by partial safety fac-

tor for loading) , whereas in checking fatigue and deformation of serviceabili-

ty limit state, the characteristic value of loading shall be used.

3. 1. 6 For checking the strength and stability of structures subjected to direct

dynamic loading, the design value of the dynamic load shall be multiplied by

an impact factor, whereas the characteristic value of the dynamic load with-

out impact factor shall be used in checking fatigue and deformation.

In the fatigue calculation of crane girders or crane trusses together with their

surge gieders, the crane load shall be dertermined by one of the cranes of

largest capacity in the bay.

e 3. 1. 7 In the design of steel structures, the characteristic value of loads, the

partial safety factor for loads, the load combination coefficient, the impact

factor of dynamic loads and the importance factor determined according to

the safety class of structures shall comply with the requirements of " Loading

Code for design of bulding structurett (GBJ9 - 8 7).

3. 1. 8 In checking the strength and stability of crane girders (or trusses) for

heavy duty cranes and the associated surge girders, and also in checking the

strength of their connections, the horizontal transverse loading from the

crane shall be multiplied by an enlargement factor given in Table 3. 1. 8.

Enlargement factor of

Horizontal Transverse Loading of the Crane

Table 3. 1. 8

3. 1. 9 In calculating working platform strutures of open- hearth, electric

furnace and converter workshops or of similar workshops, the loading caused

by repairing materials may be multiplied by a reduction factor:

for main girders 0. 85

for columns (including foundation) 0. 75

3. 2. Design Indices 3. 2. 1 The design value of steel strength ( the characteristic value of material

strength divided by the partial safety factor for resistance) shall be taken

from Table 3. 2. 1-2 according to the steel thickness or diameter (for grade

3 steel, in compliance with the classification in Table 3. 2. 1 - 1). The de-

sign value of strength of cast steel parts shall be taken from Table 3. 2. 1-3.

The design value of connection strength shall be taken from Tables

3. 2. 1- 4 through 3. 2. 1-6.

Kind of

crane

Crane with

flexible hook

crane

with

rigid

hook

For strength checking

of interconnection between

crane girder (or truss),

surge girder and column

4. 0

3. 0

2. 6

6. 0

3. 0

Lifting

capacity

(t)

5- 20

30- 275

>300

-

soaking pit

crane,

stripper

crane

or rigid

claw crane

others

For strength and stabi-

lity checking of crane

girder (or truss) and

surge girder

2. 0

1. 5

1. 3

3. 0

1. 5

Size Classification of Grade 3 Steel (mm)

Table 3. 2. 1- 1

vote: The thickness of chanwls and I- shapes refers to the web thickness of these shapes

Design Value of steel strength (N/mm2)

Table 3. 2. 1-2

Size group

Group 1

Group 2

Group 3

,\:ate: For grade 3 killed steel, the design value of strength in tension, compression, bending and

shear may be increased by 5%.

Diameter or thickness of

bars (round,

square and flat)

<40.

>40-100

I

Thickness of angles,

channels and I-shapes

<15

>15-20

>2O

steel

Thickness

of plates

<20

> 20-40

>40-50

Tension,

compression

and bending

f

215

ZOO

190

315

300

290

350

335

320

Grade

Grade3

16Mn

16Mnq

15MnV

15MnVq

Shear

f"

125

115

110

185

175

170

205

195

185

Group

group 1

group 2

group 3

- - -

- - -

Bearing on end

surface (planed

and closely fitted)

f,.

320

320

320

445

425

410

450

435

415

Thickness

or diameter

(mm) - - -

<l6 17-25

26-36

a 6 17-25

2 6- 3 6

Design Value of Cast Steel Strength (N/mrn2)

Table 3. 2. 1- 3

Design Value of Weld Strength (N/mm2)

Table 3. 2. 1- 4

Steel grade

ZG200-400

26230- 450

26270-500

26310-570

n o t e : The electrode zui3.e and flux used in automatic am? semi-automatic welding shaU be guaran-

teed that tens& strength of the deposited metal is not less than that of tlre conesponding e b

Erode used for manual welding.

Tension, compression

and bending

f

155

180

210

240

Method of

welding and

type of

electrode

Shear

f"

90

105

120

140

Automatic,

semi-

automatic

welding and

manual

welding

with

electrode

t Y P

Bearing on end surface

(planed and closeiy fitted)

fc*

260

29 0

325

370

Member material

E43xx

E50xx

E55xx

Steel

grade

grade 3

16Mn

16Mnq

15MnV

.. 5Mnvc

Fillet

weld

Tension,

zompres-

sion and

shear C

160

160

160

200

200

200

220

220

220

Compres-

sion c

215

200

190

215

300

290

350

335

320

Group

1

2

3

- - -

- -

-

ness

or diam.

(mm)

- - -

<l6 17-25

26-36

<l6 17-25

26-36

-

Shear

G

125

115

110

185

175

170

205

195

185

Butt weld Tension and

bending C

for weld

quality

of class 1 and 2

215

200

190

315

300

290

350

335

320

3

185

170

160

270

255

245

300

285

270

Design Value of Riveted Connection Strength (N/mrn2)

Table 3. 2. 1-5

.TITotes : 1. Holes made by the follouing processes belong to Class I :

1) holes drilled to Ute design diameter on the assembled members;

2) holes of design diameter driUed separately on individual elements and members by us-

ing driUing tenaphte;

3) holes drilled or punched to a smaller diometer on individual elemats and reamed aj-

terunrds to the disign diameter on the assembled member.

2. Holes that are punched or drilled withart templute to the design diameter on individual el-

ements belong to Class IZ.

Steel grade

of rivet and

member

Rivet

Member

Member matarial

ML2 or

ML3

grade 3

16Mn

16Mnq

group

Tension

(breaking

rivet

head)

f:

120

-

- - -

thickness

(mm)

Bearing f, Shear f:

Class I

holes

-

Class I

holes

185

Class 11

holes

Group

1-3

- -

Class II

holes

155

-

< l 6

17-25

26-36

-

- A

-

-

445

610

59 0

565

360

500

480

460

Design Value of Bolted Connection Strength (N/mm2)

Table 3. 2. 1 - 6

-Votes: Holes made by the following pocesses belong lo Class I :

1 ) holes dr&d lo the design diameter on the assembled membas;

2)holes drilled to the design diametw separately on individual elements and members by

Steel grade

(or property

class) of

bolts and

members

Ordinary bolt.

grade 3

steel

using d~illing template;

3 ) holes d~iUed or punched lo a smaller diameter on individual elements and ~ m e d af -

Anchor

bolts --

High -

teruu~ds lo te deaign diameter on the assembled member.

Member steel

grade 3

16Mn

Group

thick - ness

(mm>

strength

bolts in

bearing

type

Anchor

bolts

ten-

sion

f F

-

140

-

-

Ordinary

grade

8. 8

grade

10. 9

ten - sion

f P

170

-

bolts

- I -

ten - sion

ftb

170

- -

-

- - - - - - -

High - strengrh

bolts in

bearing

type joint

- I -

250

310

- joint

Grade C

shear

f:

130

- -

- -

- -

- - - - -

shear

fb,

-

-

- -

465

Mem - bers

bea - ring

f:

-

- -

- -

305

420

400

385 435

420

400

Grade A or B

bea - ring

f:

-

- -

- -

- '

-

- -

1

- - -

- -

- - - - - - -

grade 3

16Mn

16Mnq

15MnV

15Mnq

- -

shear

1- 3 - - - - - -

-

- 1 ib% -

bearing

- 1 l a0

-

<16 17- 95

26-36 <16

17- 25

26-36

- - -

- -

400

550

530

510 570

550

530

665

640

615

(hole

fb,

170

-

- -

- - - - - - -

class I)

f!

-

-

I

3. 2. 2 The design value of strength specified in Clause 3. 2. 1 shall be multiplied by a relevant reduction factor in the following situations of

member and connection calculation :

1. Single angle connected by one leg

1) for checking member and connection strength as axially loaded

0. 85 2)for checking stability as an axially loaded compression member

Equal leg angles 0. 6+0. 0015A, but not larger than 1. 0 Unequal leg angles connected by short leg 0. 54-0. 0025h, but not larger than 1. 0 Unequal leg angles connected by long leg 0. 7

where A is the slenderness ratio , which is determined by the least radius of

gyration for a single angle compression member without intermediate connec-

tion. Assume A=20 when h<20. 2. Erection field welded and riveted connection made in unfavorable condi-

tion high above the ground 0. 9

3. Countersunk and semicountersunk riveted connection 0. 8 -1bte : When seve~al of these situations occour simultaneously, the relevant reduction factors shall be multiplied

.mccessively.

3. 2. 3. The indices of physical properties of rolled and cast steel shall be tak-

en according to Table 3. 2. 3.

Indices of Physical Properties of Rolled and Cast Steel

Table 3. 2. 3

Oensity

(Kg/m3)

Coefficient of

linear expansion

(per C

Modulus of

elasticity

E (N/mmz)

Shear modulus

G (N/mm2)

3 . 3 . Requirements for Deformation of Structure

3. 3. 1 iieduction of sectional area by bolt ( or rivet) holes may not be taken

into account in the deformation calculation of steel structures.

3. 3. 2 The deflection of a flexual member shall not exceed the relevant al- ~ lowable value listed in Table 3. 3. 2. i

Allowable Deflection of flexural members

I I Crane girders and crane trusses I I

Table 3. 3. 2

1 ) for hand operated cranes and monorails (including

underslung cranes)

2 ) for bridge cranes of medium duty with lifting capability

Q<50t and those of light duty

3) for bridge cranes of medium duty with lifting capability

Q>50t and those of heavy duty

Allowable

deflection

Item

No.

1 3 ] Bean-rails for hand operated or electric hoists 1 1/400 1

Type of member

2

Beams of working platform under track with heavy rail

(weighing 38kg/m or more)

Beams of working platform under track with light rail

(weighing 24kg/m or less)

I Roof girders or roof trusses with underslung electric beam crane

(only for calculation under variable loading) 1/500

Beams of floor and working platform (except Item 4 ) ,

platform slabs

1 ) main beam (including beam with underslung hoisting

equipment)

2) beam with plastered ceiling (only for calculation

under variable load)

3) beam other than Items 1 ) and 2) (including stair bearn)

4) platform slabs

Purlins under roofing of

1 ) corrugated iron and asbestos sheet with no dust

accumulation

2) profiled steel, corrugated iron and asbestos sheets

with dust accumulation

3) other types

Members of wall framing

1) stud

2) wind truss (acting as support to continuous stud)

3) horizontal girt in masonry wall

4 ) horizontal girt for cladding of profiled steel,

corrugated iron and asbestos sheet

5) girt for glass window (vertical and horizontal)

-170te : 1 denotes the span length o f a flemral member ( for cantilever beam and overhanging bearn,

I is t u s e the length o f cantilever or overhang).

3. 3. 3 The horizontal deflection at the top of a multistory framed structure

under wind action should not exceed 1/500 of the total height of the struc-

ture, The story drift should not exceed 1/400 of the story height. ~l'ote: For mullistory flamed sCructure o f a civil building requiring refined illdoor h a t k m , the

ratio o f the story dr i f t to story height should k reduced appropriately. For multistory stmc-

ture without partition mu, the story d r i f t m y not k limited.

3. 3. 4 Ln mill buildings equipped with heavy duty cranes, the deflection of

the surge girder on each side of the bay, caused by horizontal load from one - 1 5 -

of the cranes of largest capacity, should not exceed 1/2200 of its span

le!:g:h.

3. 3. 5 For a mill building equipped with heavy duty cranes and for a n open 3

gantry equipped with medium or heavy duty cranes, the calculated deforma-

tion of the column caused by the horizontal ioad from one of the cranes of .. largest capacity, at the top elevation of the crane girder or crane truss, shall

not exceed the relevant allowable value given in Table 3. 3. 5.

Allowable Calculated Value of column Deformation

Table 3. 3. 5

Type of deformation scheme scheme

Transverse deformation of mill building

column

Calculation based on

I I

Transverse deformation of apen gantry

column

Note: 1. HT denotes the height from the bottom surface of the col- ~ umn base to the top of the crane girder or truss. I

2. In the calculation of longitudinal deflection of mill building or open gantry

plane structure

H~/1250

H~/2500 I - Longitudinal deformation of columns of

mill building and open gantry

column, the longitudinal load of the crane may be distributed to all the in-

ter - column bracings or longitudinal frames in a section between expan-

space structure

H~/2000

HT/4000

sion joints.

3. For mill buildings equipped with soaking pit cranes, stripper cranes or rigid

claw cranes, the allowable calculated deformation of the columns shall be

reduced by 10%.

4 Calculation of flexural members

4. 1 Strength

4. 1. 1 The moment capacity of solid web members bent in their prnicipal

planes shall be checked as follows :

1. For inembers subjected to static loading or indirect dynamic loading:

where M, , M, - bending moment about x - and y - axis (for I -section,

x -axis is the strong axis and y the weak axis) ;

Wm , Wn, - net section modulus about x - and y - axis ;

I,,, 11, - plasticity adaptation factor, 1% = 1. 05, yr = 1. 20

for I -section, JJ, , j), = 1. 05 for box section,

see Table 5. 2. 1 for other sections ;

f - design value of bending strength of the steel.

When the ratio of the free outstand of the compression flange to its thickness

is larger than 13 - ( but not exceeding the value required in v' 2:,5 Clause 4. 3. 9 ) , ?,shall be katen as I. 0. fgis the yield strength of the materi-

al, equal to 2 35 AT/mm2 for grade 3 steel, 345 N/mm 2 for 16Mn and 16Mnq

steel and 390 N / m m 2 for 15MnV and 15MnVq steel.

2. For members subjected to direct dynamic loading, Formula (4. 1. 1) is

still valid, but 11, = 11, = 1. 0 shall be used.

4. 1. 2 The shear capacity of solid web members bent in their principal plane

shall be checked by the following formula

where V - shear force in the calculated section along the plane of web;

S - static moment of that part of the gross section above the

location where shear stress is calculated about the neutral axis;

I - gross moment of inertia of the section; - 17 -

t, - web thickness;

j,2 - design vaiue or' shear strengtn OF steei.

4. 1. 3 When a concentrated load is acting along the web plane on the upper

flange of the beam, and that no bearing stiffener is provided at the loading lo-

cation, the local compressive stress of the web at the upper edge of its effec-

tive depth shall be computed as follows:

where F - concentrated load(taking into account the impact factor in case

of dynamic loading) ;

$ - factor, $ = 1. 3 5 for heavy duty crane girder ; $ = 1. 0 for

other beams and girders;

I=-- the assumed distribution length of the concentrated load at the

1; qqpr+d$A,of the effective web depth taken as (4. I. 3 - 2) where a -bearing length of concentrated load along the beam span,

taken as 5cm for crane girder;

h, - the distance from the top of rail of crane girders (or top of the

beam for those without rail) to the rail) to the upper edge of the

effective web depth.

At the beam support, when no bearing stiffener is provided, the local com-

pressive stress in the web at its lower edge of effective depth shall also be

checked by Formula ( 4. 1. 3 - 1 ) , with .J, taken as 1. 0. T i e distribution

length of the end reaction shall be determined with reference to Formula

(4. 1. 3- 2) and according to the dimensions of the support. -Tote : The effective web depth i s :

For rolled &ams:the distance &tween the toes of the filleki joining the web with the upper and l o w

flanges ;

F m welded girders: the depth o f the web 4

For riveted (or high - strength bolted) girder : the distance betueen the neurest gauge lines of r ive ts

( o r

high-strength bolt) connecting the web with the upper and l o u w fEanges(see Fig. 4. 3. 1 ) .

4. 1. 4. In case comparatively'large normal stress a ,shear stress z , and local

compressive stress a, (or comparatively large a and z ) exist simultaneously at - 18 -

the edge of the effective we5 depth of built-up girders,

e. g. at the support of the continuous girder or at a section where the flange

changes its dimensions, the reduced stress shall be checked by the following

expression

d o 2 f oc2 - u oc+ 3 . ~ ~ < P l f ( 4 . 1 . 4 - 1 )

where u , z , oc -normal stress, shear stress and local compressive stress

cccuring simultaneously at a same point on the edge

of effective we5 depth. T and uc are calculated by

Formulas (4. 1. 2) and (4. 1. 3 - 1)respectively , while , cr is determined as follows

M o = -yl (4 .1 .4 - 2)

I n

u and u, are taken as positive whiie being tensile and negative while compres-

sive ;

I, - net mament of inertia of the beam section;

yl - distance from the calculated points to the neutral axis of the

beam section ;

- coefficient, P1 = 1. 2 when u and uc are of different signs,

pl = 1. 1 when o and oc are of the same sign or

when (7, = 0.

4 . 2 Overall stability

4. 2. 1 Calculation of the overall stability of the beams may not be needed

when one of the following situations takes place:

1. A rigid decking (reinforced concrete slab or steel plate) is securely con-

nected to the compression flange of the beam, thus being able to prevent its

lateral deflection ; - 2. The ratio of the unsupported length , 11, of the compression flange of a

simply supported I-section beam to the flange width bl does not exceed the

values given in Table 4. 2. 1.

l1 is equal to the span length for beams without intermediate lateral support

and is taken as the distance between lateral supports for beam with intermedi- ,h-

- 19 -

tae lateral supports (the end supports of the beams are regarded as laterally

Maximum ll/S1 values of I-section simp!y supported

beams to avoid checking for. overall stability

1 Grade 3 1 13 20 1 16 I

Table 4. 2. 1

J-otes: 1. The maximu~n i l j b l value o f beams made o f steel grade other than those shoun in Table

4. 2. 1 shall be that o f grade 3 steel multiplied by .,/m . 3. Detailing rneasures shall be taken to present torsion of the a d support section.

Steel

4. 2. 2 Except for the situations specified in the 4. 2. 1, members bent in their

pricipal planes of the largest rigidity shall be checked for overall stability as

I

the upger flange the lower flange load acting anywhere ,

Beams without intermediate lateral

support, load acting at

where M , - maximum bending moment about the strong axis ;

Beams with intermediate

lateral support,

Wz - gross section modulus of the beam with respect to the 1 ,

compression flange ;

q~~ - overall stability factor determined according to Appendix 1. -170te: Same as .ATote 2 o f Clause 4. 2. 1.

4. 2. 3 Except for the situations specified in the Clause 4. 2. 1 , I-section

members bent in their two principal planes shall be checked for overall stabili-

ty as follows :

where W z , WY -gross section modulus about x - and y - axis with

recpect to compression fibers ;

tpb - overall stability factor for members bent about the strong axis, - 20 -

same as in Clause 4. 2. 2. -\‘ate: S u ~ n e us -1ote 2 o j Clause 4. 2. 1. ,

4. 2. 4 Simply supported beam of box section not conforming to the first situ- 3 ation specified in Clause "a. 2. 1 shall nave its cross section dimensions so that

h 11 - < 6 (see Fig. 4. 2. 4 ) and that the value of - shall not exceed bo 60

95 for grade 3 steel

65 for 16hIn anci 16iiAnq s ~ e e !

5 7 for 15Mnv and l5Mnvq steel

Box section simply supported beams fulfilling the above requirement should

not be checked for overall stability. 1 235

-Yote : value for beams o j other steel grades shall not ezceed 9 5 (-). bo f J

4. 2. 5 Lateral bracings for reducing the unsupported Ienglh cf :he csmpres-

sion flange of a beam shall have their axial force determined by a lateral force

equal to

where P-f - cross-sectional area of the compression flange of the beam.

4. 3 Local stability

4. 3. 1 Stiffeners shall be provided for webs of built-up girders to prevent

local buckling in accordance with the following provisions (Fig. 4. 3. 1 ) :

' O , stiffeners 1. When-< 80 1

t w should be provided for girders with

a, # 0 in accordance with detailing

requirements, but may be not

provided for girders without local L-4- compressive stress ( CT, = 0 ). Figure 4. 2. 4

235 ho 2. When80 -<-<I70 - , transverse stiffeners shall be provided t ,

with spacings conforming to the requirements of Clause 4. 3. 2 ( For girders

without local compressive stress calculation may not be required if

ho 3. When - > 17 0 transverse stiffeners shall be provided, besides, lon- t,

gitudinal stiffeners and also short stiffeners , if necessary, shall be provided

in the compression zone of the web. All these shall be calculated according to

the requirements of Clause 4. 3. 2. In the above, ho is the effective web depth , t, is the web thickness.

4. Bearing stiffeners shall be provided at girder supports and anywhere a

fixed and comparatively large concentrated load is applied on the upper

flange. They shall be calculated according to Clause 4. 3. 8.

4. 3. 2 Stiffener spacing shall be determined according to Clauses 4. 3. 3 through 4. 3. 6 for girders without local compressive stress ( uC = 0) and for

simply supported crane girders, when transverse stiffeners alone or together

with longitudinal stiffeners are provided to the web. Local stability of the

web of girders other than the above mentioned shall be checked according to

Appendix 2.

. . .. ._ j . , " . . ." . . . ." ,

I . . . ., . . , - ? . 1 . . . . I . . . ..

Figure 4. 3. 1 Layout of stiffeners

1 - transverse stiffeners ; 2 -longitudinal stiffeners ; 3 - short stiffeners.

4. 3. 3 When the web of girders without local compressive stress ( u, = 0) are

strengthened by transverse stiffeners alone, their spacing, a , shall satisfy the

following requirements :

1. a shall not exceed the maximum spacing specified in Clause 4. 3. 7

where z - average shear stress ( in N/mm2 ) due to the maximum

shear force in the considered segment of the girder, namely v a = - , hw being the web depth ;

h w tw

q - enlargement factor due to the effect of u ,given in

Table 4. 3. 3.

u - .

is the compressive bending stress at the edge of effective I

depth in the same cross-section where ais computed, I being

the gross moment of inertia of the girder and yl the distance

from the compression edge of effective web depth to the neutral

axis.

q value Table 4. 3. 3

-1,te: q calue in this table is given by the follouing ezpresswn:

The spacing, a , shall not exeed the maximum value specified in Clause

4. 3. 7 when the right hand side of Formula (4. 3. 3 - 1) has a value larger

than this maximum value.

4. 3. 4 When the webs of girders without local compressive stress ( o, = 0 )

are strengthened simutaneously by transverse and longitudinal stiffeners

(Fig. 4. 3. 1. b , c) , the distance from the compression edge of effective web

ho ho depth to the longitudinal stiffener hl shall be within the range of - to - and 5 4

satisfy the following requirement

4 where 0 - compressive bending stress (in N/mm2 ) at the edge of effective

web depth due to the maximum moment in the considered

Mmuyl segment of the girder, cr = - I '

The spacing, a , of the transverse stiffeners is still determined according to

Clauses 4. 3. 3 and 4. 3. 7 , but ho shall be replaced by he and 7

taken as 1.0. -

4. 3. 5 When the webs of simply supported crane girders are strengthened by I

tranverse stiffeners only, rhe stiffener spacing, a , shall satisfy simutaneousiy

the following two formulas :

where kl , k2 - parameters given in Table 4. 3. 5 - 1 ;

k 3 , k4 - parameters given in Table 4. 3. 5- 2 ; I z - average shear stress(in N/mm2 ) of the web at the location of

vmz maximum shear force of the girder, z = - . h w t w

a - compressive bending stress (in N/mmz ) at the edge of effective I

I

web depth due to the maximum moment of the girder , I

a, - local compressive stress( in N / m m 2 ) at the edge of effective i web depth computed by Formula(4. 1. 3-1) with !P =l. 0

in all cases.

Values of kl and k2 Table 4. 3, 5- 1

Values of k3 and k4 Table 4. 3. 5-2

The spacing, n ,shall be taken equal to 2h0 when the right hand sides of For-

mulas ( 4. 3. 5 - 1 ) and (4. 3. 5 - 2) have values larger than 2ho , or have a

denominator of negative sign.

For crane girders of varying cross - section, the value, a , shall be deter-

mined in accordance with the following provisions when the length of the end 1

segment with varying section does not exceed - of the span length of the 6

girder :

1. Crane girders with varying web height: the value, a , of the end segment

with varying height shall be determined by the Formula (4. 3. 5 - 1 ) , where-

in ho is the average effective web depth, z is the maximum average shear stress

in the web of the end segment of the.girder. The value, a , of the segment

with constant cross - section shall satisfy the requirements of both Formulas

( 4. 3. 5 - 1) and (4. 3. 5 - 2) , with zl being the average shear stress of the

web at the junction of the two segments.

2. Crane girders with flanges changed at certain sections : the value, a , within the segment from the end of the girder to the location where the sec-

tion changes, shall satisfy the requirements of both Formulas (4. 3. 5 - 1) and (4. 3. 5 - 2) wherein a is the compressive bending stress at the edge of

effective web depth in that cross-section. At the same time' the values of kg,

k4 taken from Table 4. 3. 5- 2 shall be multiplied by 0. 75. The value, a , in

the middle segment with constant section shall satisfy the requirements of - 27 -

both Formulas (4. 3. 5 - 1 ) and (4. 3. 5 - 2) , wherein T is the average shear

srress of the web at the location where the cross-section changes.

.?

4. 3. 6 When the webs of crane girders are strengthened simultaneously by

transverse and longitudinal stiffeners (Fig. 4. 3. 1. b, c) , the distance from

- the longitudinal stiffener to the compression edge of effective web depth, hl , ho ho shall be within the range of - to and shall satisfy the following require- 4 "

ac for -< 0 .4 a

where a , a, - as defined in Clause 4. 3. 5.

Short stiffeners shall be provided in the compression zone of the web

(Fig. 4. 3. 1. d ) and calculated in accordance with Appendix 2 when the right

ho hand side of Formula (4. 3. 6-1) or (4. 3. 6-2) has a value less than - . 5

The spacing, a , of transverse stiffeners shall be determined by Formula

( 4. 3. 5 - 1 ) but replacing h~ by he and replacing a, of Table 4. 3. 5 - 1 by

0. 30, . Take a < 2hz in case the right hand side of Formula (4. 3. 5 - 1 ) has

a value larger than 2h2 or has a denominator of negative sign.

In determining the value, a , of the segment of varying web height of crane

girders with longitudinal stiffener, h2 shall be the average effective depth of

the lower panel of the web? T shall be the average shear stress of the web at

the end of the beam. In determining the value, a ,in the region of constant

cross-section, T shall be the average shear stress of the web at the junction

of the two segments. h determining the value, a , of crane girders with

flange changed at certain sections, T shall be the average shear stress of the

web at the end of the girder.

4. 3. 7 Stiffeners should preferably be placed in pairs on each side of the

web. Stiffeners on one side of the web are also allowed. But for bearing

stiffeners and stiffeners of heavy duty crane girder, stiffeners on one side - 28 -

shall not be used.

The minimum spacing of the iransverse stiffeners is 0. 5Ao , the maximum

spacing is 2izo(2. 5ho may be used for girders without loml compressivs stress

h 0 when - \( 1 0 0 ). tw

Transverse stiffeners in pairs, made of flats, shall satisfy the following re-

quirements :

outstanding width

thickness

The outstanding width of transverse stiffeners on one side shall be larger than

1. 2 times that obtained from Formula (4. 3. 7 - 1 ) . Its thickness shall not 1

be less than - of the outstanding width. 15

For webs strengthened simultaneously by transverse and longitudinal stiffen-

ers, the dimensions of the transverse stiffener shall meet the above require-

ments and its moment of inertia, I2 , shall also conform to the following re-

quirement :

1 2 ), 3hotw3 (4.3.7 - 3)

The moment of inertia of the longitudinal stiffener shall satisfy the following

requirement : ~ a

for , < 0.85 (4.3.7 - 4)

The minimum spacing of the short stiffeners is 0. 75hl . Their outstanding i width shall be 0. 7 - 1. 0 times that of the transverse stiffeners, their thick-

1 ness shall not be less than - of the outstanding width.

15 ..\-ate: 1. Stiffeners .made of structural shapes(1- ,[- section, angk with its tip web?& to the web) shall

have a moment of i m t i a not less than that of the flot stiffeners.

2 . The mnnent of inertia of stiffeners in pairs shall be computed about the center line of the

u ~ b . The moment of inertia of stiffeners on one side shall be computed about the edge line of the

web where the stiffener is connected.

4 . 3 . 8 The bearing stiffeners of girders shall be checked for buckling'about - 29 -

the web axis as an axially loaded strut subjected to end reaction or fixed con-

centrated 102d. The crcss section of this memker shall comprise tbai of the

stiffener plus a portion of the web 15t, in width on each side of the

stiffener. The effective length of the strut shall be taken equal to ho . Checking shall also be carried out at the end of bearing stiffeners for bearing

strength when the end is planed and closely fitted (meeting also the require-

ment of Clause 8. 4. 13 for extended flanged stiffener) , and for weld

strength when the end is welded.

i 4. 3. 9 The ratio of the free outstand of a compression flange b to its thickness

t shall satisfy the following requirement: I

The ratio of the compression flange width b of a box girder between the two I web plates to its thickness shall satisfy the following requirement:

I

When longitudinal stiffeners are provided for the compression flange of the ~ box girder ? bo in Formula (4. 3. 9 - 2) shall be that part of the flange width 1 between one web and the longitudinal stiffener. 1 ..Vote: The f ~ e e outstand b o f the flange shall be tcken as follows: the distance from the face o f the web to the

flange tip for welded members g the distance from the toe of the fillet to the flange tip for Tolled

r'

5 . Calculation of axially loaded members and members sub- jected to combined axial load and bending

5 . 1 Axially loaded members

5. 1. 1 The strength of members subjected to axial tension or compression

shall be checked as follows:

where &%T - axi'al tension or compression ;

A , - net cross-sectional area.

The strength of the member at a high strength bolted friction type joint shall

be checked by the following formulas

and

where n - number of high strength bolts of one end of the member at a ,

joint or a splice;

nl -number of high strength bolts on the computed section (outermost

line of bolts) ;

A - gross sectional area of the member.

5. 1. 2 The stability of axially loaded compression solid web members shall be

checked as follows

where g, - stability factor of axially loaded compression members shall be

taken from Appendix 3 in accordance with the classification of

sections in Table 5. 1. 2. - 31 -

Classification of sections of

axially loaded compression members

Table 5. 1. 2

..Vote : Channels used as cornponenkr of kc& or bathmd members shall belong to Class b u p checking c o m p

nent buckling about the & perpendimh~ to the webs.

Class

a

b

*

5. 1. 3 The stability of laced or battened members in axial compression shall

. still be checked by Formula (5. 1. 2), using the equivalent slenderness ratio - 32 -

. -

Shape of sections and corresponding buckling axis

ta( rolled ,b/h<O. 8 , x-I-~T. 1 about x-axis

k$l rolled ,b/h<O. 8 ,

li about y-axis Ul

welded, with flame

cut flange edges, 111. " about x- & y-axis

rolled ,about

x- &y-axis

* rolled equal

, angle,

about x- & y-axis

rolled or welded,

about y-axis about x-axis

welded,

about x- & y-axis UI

laced or battened,

about x- & y-axis

0 rolled,

about any axis

h /d rolled ,b/h>O. 8 , =-T=T *-'- abour x- & y-axis

welded, with rolled

Z- , I or sheared flange

edges, about x-axis

+- rolled, about

+ Y x- 8L y- axis

welded,

=-&i 0 111

about any axis

rolled or welded,

C

welded, with rolled

or sheared flange

lu 1 edges, about y-axis

rolled or welded,

rolled or welded

'U about y-axis

non-symmetric sections,

about any axis . welded solid web sections with plate

element thicker than 4 0mm , about any axis

- for buckling about the open web axis ( x -axis in I

Fig. 5. 1. 3a and x - and y -axes in Fig. 5. 1. 3b,c).

The equivalent slenderness ratio shall be computed as follows:

1. Members builtup of two components (Fig. 5. 1. 3a) I - - . -

For battened members

For laced members I

where A, - slenderness ratio of the whole members about the x -axis; , .

A, - slenderness ratio of the components about their weak axis 1 - 1 , . the unsupported length taken equal to the clear spacing of bat-

tens for welded member, and equal to the distance between end

bolts of adjacent battens for bolted members.

A1, - sum of gross sectional area of the lacings perpendicular to the

x -axis in a section of the member.

2. Members builtup of four components (Fig. 5. 1. 3b)

For battened members

i I

For laced members . r

where 3, - slenderness ratio of the whole member about the y-axis;

AlY - sum of gross sectional area of the lacings perpendicular to the

y -axis in a section of the member.

3. Laced members with three cbmponents(Fig. 5. 1. 3c) - 33 -

where Al - sum of the gross sectional area of all the lacings in a section of

the member.

0 - angle between a lacing plane and the x -axis in a section of

{he member.

(a) (b) (c)

Fig. 5. 1. 3 Section of laced or battened members -Vote : 1 . The 2inea.r stiffness o f the battens shall comform to the ~equi~ementa of Clause 8 . 4 . 1 .

2 . The angle betupen the lacing and the member azis shall be within the Tange of 40°-70°.

5. 1. 4 The slenderness ratio of the components of laced members in axial

compression shall not exceed 0. 7 times Am, , which is the larger of slender-

ness ratios of the members in two directions (the equivalent slenderness ratio

shall be taken for open-web axis) ;the slenderness ratio of the components

of battened members in axial compression shall not exceed 40 nor 0. 5& ( kYI, is taken equal to 50 in case it is less than 50).

5. 1. 5 Members composed of t w h angles or twin channels separated by fillers , .

.'L may be considered as solid ones in calculation provided that the spacing of the - 34 -

/' fillers is less than

4 0i for compression members

8 0i for tension members

where i is the radius of gyration of one component and shall be taken as fol-

2 lows :

1. i is taken about the centroidal axis parallel to the fillers when the twin

u angles or channels are combined as shown in Fig. 5. 11 5a, b.

2. i is taken about the weak axis when the two angles are combined in a

cruciform section as shown in Fig. 5 . 1. 5c.

The number of fillers of a compression member between two adjacent lateral-

1 ly supported points shall not be less than 2.

Fig. 5. 1. 5 Axis for computing i

5. 1. 6 Axially loaded compression members shall be computed according to

the following shear force

This shear force V may be considered as constant along the member length.

The shear force T7 shall be distributed to relevant lacing or batten planes(a1so

to planes of solid plate element if there exists any) for laced or battened

members in axial compression.

5. 1. 7 Bracing bars used for reducing the unsupported length of axially load-

ed compression members shall be proportioned to carry an axial force deter-

mined from the shear force TJ (as a lateral force) of the supported members.

V may be computed by Formula (5. 1. 6). - 35 -

5. 2 Members subjected to combined axial load and bendin%

5. 2. 1 The strength of members subjected to combined axial load and mo-

ments acting in principal planes shall be checked as follows:

I. Under static loading or indirect dynamic loading

w hereyZ, y7 - plasticity adaptation factors given in Table 5. 2. 1.

2. Under direct dynamic load : Formula (5. 2. 1 ) are still valid, but yz and yg t i shall be taken epual to 1. 0.

Plasticity adaption factors

Tabie 5. 2. j.

A"te : when the ~ a t i o of fTee outstand o f the compression f lunge of a beam - column to its thickness is lu~ger

M a n 13 @ , but aot ezceedinp the value regui~ed in Chuse 5. 4 . 1, Y. shad be taken as 1. 0.

kern

No.

1

1 2

3

I

4

5

6

7

8

5. 2. 2 Solid web beam - columns bent in their plane of symmetric axis

(about x -axis) shall have their stabitity checked as follows.

Cross-sectional shapes

1. In - plane stability :

-- ,I/ I YI I Y I 3 =-Ez .-T-x rgEI UI II' Iv 71;

UI .--'. I

1. 05

1. 2

1. 05

1. 2

I I

1. 05

1. 2

1. 15

1. 05

1. 0

11 l

UI ut

=-$-j-r =-@-=

r- .%L%

v I

;Yi r-1. . I-=;je ..t

'Lj--4'

I

y,, = 1. 05

y,=l. 3

1.2

1. 15

1. 0

where N - axial compression in the calculated portion of the member;

pz - stability factor of axially loaded compression members

buckling in the plane of bending ; I I

M , - maximun moment in the calculated portion of the member ;

n2EA NEz - Euler critical load , NEz = -

2 ;

W1, - gross section modulus referred to the more compressed fiber ..

in the plane of bending ;

#?- - factor of equivalent moment, taken as follows:

1 ) #?- =l. 0, for columns of frames with sidesway in the

plane of bending and for cantilevers.

2) for columns of frames without sidesway and for member

supported at the two ends:

M2 a. without any transverse loads, 8, = 0. 65 + 0. 35 - , M I

but not less than 0. 4 , where M I and M2 are end mo-

ments taken as of the same sign for members bent in single curvature ( without inflexion point) and of dif-

ferent signs for members bent in reverse curvatures (

with inflexion point), I M I 1 2 I M2 ( 8

b. with end moments combined with transverse loads , Bm = 1. 0 for members bent in single curvature and

Bm = 0. 85 for members bent in reverse curvatures;

c. with transverse loads and without end moments, N BmZ = 1 - 0. 2 - for concentrated load at midspan ,

NEZ and p,,,= = 1. 0 for other loading cases.

Beam-columns of monosymmetric sections shown in Items 3 and 4 of

Table 5. 2. 1 shall be checked by the following formula in addition to . ~ Formula (5. 2. 2- 1) in case the bending moment in the plane of symmetric ~ axis causes compression on the larger flange:

where Wz, -gross section modulus referred to the smaller flange. ~ 2. Out - of - plane stability : 1

where vY -stability factor of axially loaded compression members buckling 1 out of the plane of M, ; !

vb -overall stability factor of beams under uniform bending

determined in accordance with Clause Al. 5 of Appendix 1 for I- and T-sections , and taken asvb = 1. 4 for box

sections ; d I M, - maximum moment in the calculated member portion; I BLr -factor of equivalent moment taken as follows:

. , 1) For members with lateral supports, #?& shall be determined

according to loading and internal force situation in the

member portion between two adjacent supporting points as t

follows : - a. in the case of no transverse loads within the calculated , I

M1 portion, B, = 0. 65 + 0, 35 - but not less than 0. 4 , M2

where MI and M2 are end momonts in the plane of

bending, taken as of the same sign when causing a single

curvature and of different sign when causing reverse

curvature ; I MI I I Mz I ; b. in the case of having end moments combined with

transverse loads: B, = 1. 0 for member portions bent I in single curvature, B, = 0. 85 for those bent in reverse I curvatures ; I

c. in the case of having transverse loads and no end

moment : B, = 1. 0 . 2) For cantilevers, B, = 1 . 0 .

.Voles: 1 . Frames connected lo a bracing system such a s bracing mPmbers, shear d and elevator well so that

the stiffness o f the system against k a l displacement is af hast 5 limes of (Aot o f t.h.e h e

frames m e regarded as frames udhout sideauwg.

2. Fraines nd having any bracing system or provided of ud.h bracing system not sotkfgiag the above

~equ i~ement aTe ~egarded as f ~ a m e s with sidesukay. ~ 5. 2. 3 Laced or battened beam-columns bent about the open web axis( x - axis) shall be checked for in-plane stability by the following formula: ,

Iz I

where W I z = -, Iz being the moment of inertia of the gross area about the x 90

-axis, yo being the distance from the x '-axis to the axis of the more com- ~ pressed component or to the outside face of this component, whichever is

larger; g>, and NEz shall be determined using the equivalent slenderness ratio. i The overall out - of - plane stability of the member may not be checked in

this case, but the stability of components shall be checked. The axial force of

these components shall be determined as in the chords of trusses. For battened

columns, bending of the components due to shear force shall be taken into ac-

count.

5. 2. 4 Laced or battened beam-columns bent about the solid web axis shall

have their in -plane and out -of -plane stability checked in the same way as

solid web members,but the equivalent slenderness ratios shall be used for out

-of-plane overall stability calculation and ph taken as 1. 0.

5. 2. 5 Doubly symmetrical I- and box section beam-columns bent in two

principal planes, shall be checked for stability by the following formulas:

where v,, , qp. - stability factors of axially loaded compression members

about the strong axis x - x and the weak axis y - y

respectively ; - 10 -

yh , ybg - overall stability factors of beams under uniform bending :

for I-section, cpb, may be determined in accordance with

Clause Al. 5 of Appendix 1 , cpb, may be taken as

1. 0 ; for box section cph = ybl = 1 . 4 may be used ; '

M, ,My - maximum bending moment about the strong and the weak

axis, respectively, in the calculated member portion 4 EA EA N. , N, - Euler critical loads, N , = n2 NE, = ?rZ ;

W,, , W,, - gross section modulus about the strong and the weak

axis, respectively ;

P,,, , P,,,r - factors of equivalent moment used for calculation of in-

plane stability in accordance with Clause 5. 2. 2 ;

pL',Pt,. - factors of equivalent moment used for calculation of out-

of -plane stability in accordance with Clause 5. 2. 2.

5. 2. 6 The stability of laced (or battened) beam-columns with two compo-

nents bent in two principal planes shall be checked as follows:

I . Overall stability

2. Component stability

The axial force of a component due to Nand M, shall be determined as in the

chord member of a truss (Fig. 5. 2. 6). M, shall be distributed to two compo-

nents according to Formulas (5. 2. 6-2) and ( 5 . 2. 6-31 (see

Fig. 5. 2. 6). The stability of the component shall then be checked according

to Clause 5. 2. 2.

Component 1,

Component 2 ,

where 1 1 , I2 - moment of inertia about the y-axis of components 1 and 2

respectively ;

~ 1 , y2 - distance from x - x axis to the centroidal axes of

components 1 and 2 respectively.

Fig. 5. 2. 6 Section of laced or battened member

5. 2. 7 The lacing bars or battens of beam-columns shall be checked by us-

ing the actual shear force of the member or the shear force given by Formula

(5. 1. 6 ) , whichever is larger.

5. 2. 8 Bracing bar for reducing the lateral unsupported length of a beam- ',

column out of the plane of bending shall be proportioned to carry an axial I

force due to the lateral force given by Formula(4. 2. 5) where A, is the area

of the compression flange (for solid web members) or of the compression

component (for laced or battened members).

5 . 3 Effective length and allowable slenderness ratio

5. 3. 1 The effective length of chord members and single system web members

of trusses shall be taken as those given in Table 5. 3. 1.

Fig. 5. 3. 1 Chord member of truss with

unequal axial compression between laterally supported points a -

Effective length lo of truss chords and

single system web members

-\bks: 1 . I -geometric length of the inember (distunce betuven panel poi&)

Item

No. 1

2

3

1, -distunce betum l a t e r a l supporting p o i h of chord members.

2. The skew plane refers lo the p l o w oblique to the hvss plrme. It is applicable to d members wilh

single angle and double angle cruciform sechn ullwse pincinpl p l a n e s are ~oncoincideRt wiUl truss 4

plane .

Direction of

bending

In truss plane

Out of truss plane

In skew plane

3. For web inembers urithmt gusset p ln te ,the e f f ~ t i v e Length in any plane shall be their geometric

length.

If the distance between laterally supported points of compression chord of a

truss is equal to twice the panel length(Fig. 5. 3. 1) and that the two panels

Chord

memben

1

I I

-

have unequal compressive forces, the effective length for out - of - plane

Weh rnernhcn

End posts

1

i

1

other web rnemben

0. 81

1

0. 91

buckling shall be taken as

but not less than 0. 511

where N1 - the larger compresbive force, taken as positive ; . . . . . : . ,.. . . . . ~ .s

':. ,&? 1 . . , . I. . . ' '. .. . . j 5 , ' * : . ' ; . : ' . , . '

. - , ,, , " ,,*.a. , ,~,.?- ..,. .,zz : .,.. <; 2 : , > !:. !.' , -.:;.::: 5..;.:ii.. i,-; .:;.:< >i,, .:

Ni - thesmaller compiekive force or tensile force, taken as positive

for compression and negative for tension. .... The main compression diagonals in subdivided web system and the verticals in

K - web system shall also have their out - of -plane effective length deter-

mined by Formula ( 5. 3. 1 ) ( this length shall be 11 for main tensile

diagonals), while their in-plane effective length shall be taken as distance

\ between panel points.

7 c - . * , : b

5. 3. 2 The effective length of cross diagonals for in-plane buckling shall be

taken as the distance between a panel point and the crossing point, whereas

for out - of - plane buckling it shall be taken as follows ;

1. Compression members

when the other diagonal is in tension and both of them are uninterrupted,

0. 5Z1 when the other diagonal is in tension and one of them is interrupted and

connected by gusset plate, 0. 71 L

#~,s 1

for cases other than those cited above. 1

2. Tension members 1 3-otes: 1. 1 is the distance between panel points (the crossing point k not regwded a s a panel point).

2 . When both cross-diagonals are in compression, ideruption of either one at the crossing point

should not be recommended.

3. For detertnining the slenderness ratw o f sing& angk compression cross-diagonals in the i~ princi-

pal planes (skew pbnes) , the effective length slulll be taken equal to the dktance betwen a panel

point and the crossing point.

5. 3. 3 The in-plane effective length of an uniform section column of single

---or multi-story frames shall be taken as equal to the column length (story

height) times an effective length factor p . p shall be taken in accordance

I

with Table A4. 1 and Table A4. 2 for frames without and with sidesway re-

spectively.

5. 3. 4 The in -plane effective length of a stepped column rigidly restrained . ,

: : . . . . , . . : at,ithe:.base of a single-story mill building. shall ,be determined as followsj: . : , i -;:. .:1,~:-:.: I .. -

1. Single - stepped column

1 ) ~ f f ~ c t i v e length factor 112. for' the lower portion of the column : C . .

For columns pin-connected to the girder, ,upshall be the figures taken from

Table A4. 3 (single stepped column with free upper end) multiplied by an a p

propriate reduction factor given in Table 5. 3. 4. For columns rigidly con- ,

nected to the girder, ,up shall be the figures taken from Table A4. 4 ( single stepped column with translation free and rotation fixed upper end)

- multiplied by an appropriate reduction factor given in Table 5. 3. 4'. 2) Effective length factor ,ul for the upper portion of the column shall be

. calculated by the following formula :

where ql is a parameter calculated by the formula shown in Table A4. 3 or

A4. 4. 2. Double - stepped column

1 ) Effective length factor p3 of the lower portion of the column: For

columns pin - connected to the girder, ,us shall be the figures taken from

Table A4. 5 (double-stepped column with free upper end) multiplied by an

appropriate reduction factor given in Table 5. 3. 4. For columns rigidly connected to the girder, ,us shall be the figures taken from

Table A4. 6 (double-stepped column with translation free and rotation fixed

upper end) multiplied by an appropriate reduction factor given in

Table 5. 3. 4. 2) Effective length factors ,ul and ,u2 for the upper and middle portions shall

be calculated by the following formulas respectively :

where q,and Q - parameterscalculated by formulas' shown in Tables A4. 5 , . . ' , '

and A4. 6.

Reduction factor for the effective length of stepped columns . . in single story, mill building , . . .

5. 3. 5 the influence of the deformation of lacing bar or batten plate (or web

:Vote:

member ) and that of the variation of the section depth on the stiffness of

laced or battened columns or lattice girders (trusses) of the frame shall be

taken into account.

4 Table 5. 3.

5. 3. 6 The effective length of frame columns in the longitudinal direction of

the building (out of the frame plane) shall be taken as the distance between

supporting points restraining the out - of - plane displacement (at column

Reduction .

factor

0. 9

0. 8

0. 7

drop baU milt).

Number

of

bays

Single

Multiple

base and connection joints of crane girder, carrying trusses i. e. Jack trusses,

bracing members and logitudinal girder, etc. )

- 47 -

The reduction factor 0.9 may be used for outdm frames without roofing (e. g.

Type of the

Number of columns in a

longitudinal row within

a section between

expansion joints '

of the building

<6

>6

-

mill building

Roofing

- other than

large -size

precast R. C.

roofing slab large - size

precast R. C.

roofing slab other than

large-size

precast R. C.

roofing slab large-size

precast R. C.

roofing slab

Longitudinal

horizontal bracing

on the two sides of

the roof system

- not provided

provided

-

not prodded

provided

-

trusses) when sbressed to OT under 50% o f th&r capacities.

5. 3. 8 The slenderness ratio of tension members should not exceed the allow-

5. 3. 7 The slenderness ratio of compression members should not exceed the

allowable values given in Table 5. 3. 7.

- Allowable values of slenderness ratio

for c~mprepion,.~members , , -.. j -. ,.

Table 5. 3. 7

able values given in Table 5. 3. 8.

Allowable

values

150

200

Item

No.

1

2

- - . ..Votei i4 slenderness ~ a t w of 200 m a y be allowed far compression web members in trusses (including space'

Nomenclature of members

Columns, members of trusses and monitors.

Lacing of columns, column bracings under crane girders

or crane trusses Bracings (except column bracings under crane girders or

crane trusses). Members used to reduce the slenderness

ratio of compression members

Allowable values of slenderness ratio I for tension members

. . Table 5. 3. 8 ' . ' .

I I Structures subject to static or [ I I

I I duty crane 1 without c-e I - I

indirect dynamic loading

Item

No.

Members of 1 350 1 250 1 250 ( I I I I

Column bracing

Nomenclature

of members

under crane 1 ' girders or . I 300 , 1 , 2 0 0 ' 1 - I:

MiIl building with

aane of light or

medium d u t ~ or

I round bars) I

3

-4iot.e~: 1. FOT S ~ T U C ~ U T ~ S subject to stotic kd ing , denderuess ratw may be checked odg in vertical planes.

Mill building

with heavy

2. FOT structu~es subject to di~ect or indirect dqcnamic loading, the h s t ~qdius o f gyration skull be -

subject to

direct dynamic

loading

, .. .,,..: : ,.:,: ... .; .,., .,

crane trusses Bracings

(except Item,

2 and

used f o ~ cak~ht i im o f s~endeness ratio of a single angle tension member 5 the ~ d i w of gpatkm

about the axis pal le l to the leg sfall be used for calculation of the slenderness ratio out of the

plane of a single angle tension moss-diagonal.

.: . .:. ...

400

3. The slenderness ~ a t w of bottom rdord of crane tTusses for medium ad heavy duty crones should ) not ezceed 200.

4. In mill buildings equipped u4h s&ng pi4 crcrrm and stsipper cranes a rigid clow cranes, the

.<<,., ,

350

. . slenderness ~ a t i o of the bracings (ezcept Item 2 in thetuble) should not ezceed 300. . . .

-

5. When tension members chunge dnta compression ones under the combined action of &ad d wind

loads, the i~ s~enderness ~a l io s h d not ezceed 250.

5 . 4 Local stability of compression members

5. 4. 1 The ratio of free outstand, b , of a flange to its thickness, t , in com-

pression members shall conform to the following requirements:

1. Axially loaded compression members

where h - the larger of the slenderness ratios of the member in two

directions, taken as 30 when h < 30 ,and as 100 when h > 100 . 2. Beam - columns

Aiote: See the A70te of Clouse 4 . 3. 9 .

5. 4. 2 The ratio of effective web depth, ho , to thickness, t, , in I-section \

compression members shall conform to the following requirements:

1. Axially loaded compression menbers

where h - the larger of the slenderness ratios of the member in two direc-

tions,taken as 30 when h < 30 , and as 100 whenh > 100.

2. Beam - columns

Qnmz - a m i n where ao = 0-

an,, .- maximum' compressive stress at the edge of effective web

depth, not considering the stability factor of the member in

calculation ;

a,,,& - corresponding stress on the other edge of effective web depth, ' . '

taken as positive for compression and negative for tension;

h - slenderness ratio in the plane of bending, taken as 30 when . .

5. 4. 3 The width - to- thichness ratio of the compression flanges in box sec- - 50 -

tion compression members shall conform to the requirement of

Clause 4. 3. 9 , whereas the ratio of the effective web depth, b ,to thickness,

t. , shall conform to the following requirements:

1. . For, axially compressed members.,

ho 2. For beam- columns, the ratio - of beam shall not exceed 0. 8 times the t w

right hand side of Fomula (5. 4. 2-2) or (5. 4. 2-3), but not less than 1

-. , - 5: 4. 4 The height-to-thickness ratio of the web in T-section compression

members shall not exceed the following values : I

1. Axially loaded compression members ~ 235 1

2. Beam - columns I

for a0 < 1. 0

for uo > 1. 0

h and uo taken according to Clauses 5. 4. 1 and 5. 4. 2 respectively. 1

5. 4. 5 When the web depth - to - thichness ratio of 1 - and box - section

~ compression members does not comform to the requirements of Clause 5. 4. 2

or 5. 4. 3 , the web may be strengthened with longitudinal stiffeners, or only I l

a width of201. at each side of the web may be considered effective in I I

1 caculation of the strength and stability of members (but the whole section is I

I

I effective for determing the stability factor g, ). I I

I When longitudinal stiffeners are provided, the portion of the web between I I

the more compressed flange and the longitudinal stiffener shall have a depth I

1 - -to- thickness ratio conforming to the requirement of Clause 5. 4. 2 or

5. 4. 3. Longitudinal stiffeners shall be placed in pair on the two sodes of the web,

with an outstanding width not less than lo t , on each side, and thickness not

w less than 0. 75t, . . . . ~ . . : ' . . .: I . . . , : . . ; . . .

. . . ,. , il . - ... ,. ,. ' , . : . :.ii:. >.# , I\:..' .

1

6. Fatigue calculation

6. 1 General requirements

~ 6. 1. 1 For steel structural members (e. g. crane girders, crane trusses, b e w I of working platform, etc. ) and their connections subjected to repeated fluc-

1 tuations of dynamic loading, fatigue calculation shall be carried out when the I

number of stress cycles, n is equal to or greater than 1 05.

I

~ 6. 1. 2 The provisions in this chapter are not applicable to the fatigue calcula-

tion of structural members and their connections under special conditions (e. ~ g. members subject to surface temperatures above 150°C, members in corro-

1 sive environments of seawater, residual stresses relieved t h r o w post - weld

heat treatment, low cycle and high strain fatigue, etc. ) .

6. 1. 3 The allowable stress range method shall be used in fatigue calculation.

The stresses will be calculated in accordance with elastic state. The allowable

stress range shall be determined in accordance with the detail categories of

members and connections as well as the number of stress cycles. For the re- , gion of a member, where no tensile stress occurs in the stress cycles, fatigue

may not be checked.

6. 2 Fatigue calculation

6. 2. 1 For constant amplitude fatigue (the stress range in all stress cycles

maintains constant) calculation shall be carried out by the following formula:

do < [da] . (6.2.1 - 1)

where Aa - stress range for welded region, do = o, - amin ; reduced

stress range for non- welded regions, Aa = urn, - 0. 7amin ;

o;,,,,, - maximum tensile stress (taken as positive) of each stress - 53 -

cycle in the region considered;

u,i, - minimum tensile stress (taken as positive) or compressive

stress (taken as negative) of each stress cycle in the region

. considered ; .,, -.A ..., .a. - l .*.- . . ,. .. ' - " c . - f ~ u l -. allowable stress range, ( N/ni.liz2 ..). of constant- amplitu&e:ya-. - -

tigue, and shall be calculated by the following formula: -.. C 1 [A*] = (-)s

n (6.2.1 - 2) n - number of stress cycles;

C, /? - parameters taken from Table 6. 2. 1 according to the detail

category of members and connections in Appendix 5.

6. 2. 2 The fatigue of crane girders for heavy duty cranes and crane trusses

I , for both heavy and medium duty cranes may be regarded as constant ampli-

tude fatigue and may be calculated by the following formula:

< [ A U I ~ X I O ' (6. 2. 2) where af -equivalent coefficient of under-loading effect, adopted in

accordance with Table 6. 2. 2 - 1 ;

[ ~ u ] ~ ~ ~ o a - allowable stress range corresponding to the number of

cycles n = 2 X lo6 , adopted in accordance with

Table 6. 2. 2- 2.

3

3.26

x1O1*

3

4

2.18

~ 1 0 ' ~

3

Detail category of

members and connections

C

B

5

1.47

~ 1 0 ' ~

3 3

1

1940

x10l2

4

2

861

xl0lZ

4

6

0.96

xlO1"

7

0.65

x10l2

3

8

0.41

x10l2

3

I Equivalent coefficient of under - loading effect for

Allowable stress range (N/mm2) corresponding to

crane girder and crane truss,' cli. Table. 6. 2. 2- 1

number of cycles n = 2x1 O6 Table 6. 2. 2- 2

,*.

Crane category

Heavy duty Fane with rigid hook (e. g. ,soaking pit cpne) :

.; , , Heavy duty crane with .flexible hook ..c . .- . . : . . : . . .- - --L : . -. , . .:-. 8 ~ .. ,.

~edium' duty crane

.,. , JTote..,The allowable stress range .given in.:the table Cs. cqlculoh? by Formula (6. 2. 1 - 2). , . , . j . 2 : : - , : . .. . ; ..:: ..-,. .; . . . .

. .

6; 2 .3 or variable amplitude fatigue (the stress range in stress cycles varies

ai

1. 0

0.8 . 0. 5

Detail category of

members and connections

[hu]mo6

at random ) , if the design stress spectrum composed of the frequency distri-

bution of various loadings, the level of stress ranges and the sum of the fre-

quency distributions during the service life of the structure could be predict-

176

ed, then it may be reduced to equivalent constant amplitude fatigue,and cal-

3

118

1 ' 2

144

. . . . .. culated by .the following formula:

where Aa, - equivalent stress range of variable amplitude fatigue, determined ,

by the following formula :

4

103

Eni - expected service life of the structure expressed in number of

6

78

5

90

stress cycles ;

ni - number of stress cycles with stress range level reaching Aai with-

7

69

in the expected life.

8

59

7. Calulation of Connections

. .

7 . 1 Welded -connection . .

. .

7. 1. I Butt welds shall be calculated according to the following provisions:

1. In butt joints and T joints , the strength of the butt weld , perpendicular to

the direction of axial tensile force or compressive force, shall be calculated by I the following formula:

where N - a ~ i a l tensile force or axial compressive force ;

1, - length of weld ;

t - the thickness of the thinner part in butt joints; the thickness of I

I . . web in T joints ; . . .

I fl ,fl - design values of tensile strenth and compressive strength of

I butt welds respectively. I I

2. In butt joints and T joints, the normal stress and shear stress in butt welds

subjected to combined action of moment and shear shall be calculated sepa- l

rately. But at the location where comparatively large normal stress and shear ,. .

stress coexist (e. g. at the ends of transverse butt weld splice of a beam

web), reduced stress shall be calculated by the following formula:

..Vote : 1 . When plate elements subject to axial force are joined udh oblique butt d, and the angle 0 betwen

the weld and the acting force conforms to tg9 < 1 . 5 , the weld strength may not be cabla&a.

2 . When it is impossible to use ~un-on tabs for butt welds, the effective h g t h o f each weld shnU be

taken as the length of uvld minus 10 mm.

7. 1. 2 The strength of right -angle fillet welds (Fig. 7. 1. 2) shall be calcu-

lated by the following formulas :

1. Under the action of tensile ,compressive or shear force passing through the

centroid of welds : - 56 -

1 ) When the force is perpendicular to the direction of weld length, I

2 ) When the force is parallel to the direction of weld length,

.- 2. Under the action of other forces or the action of combined forces, at the

location of combined a j and z j :

I I In Formulas (7. 1 .2-1) through (7 .1 .2- 3) :

a j - stress perpendicular to the direction of weld length, calculated on the

effective section (h,l,) of weld ;

z j - shear stress along the direction of weld length ,caculated on the effective

section of weld ;

he - effective throat thickness of fillet weld, being equal to 0. 7hj for right - angle fillet weld, hj being the lesser leg size;

I, - effective length of fillet weld, taken as its actual length minus 10 nun for each weld;

fi - design value of strength for fillet welds;

pj - enlargement coefficient for design value of the transverse fillet weld " *. A strength: for structures subject to static loading and indirect dynamic

loading, Pf = 1. 22 ; for structuKres subject to direct dynamic load-

ing, pj = 1 . 0 .

Figure 7.1. 2 Sections of right-angle fillet weld

7. 1. 3 The strength of oblique-angle fillet weld (Fig. 7. 1. 3) shall be cal-

culated by Formulas (7. l. 2 - l) through (7. l. 2 - 3) , but using a pt = 1. 0 , and its effective throat thickness being : he = hf cos - , when 2 -

a >90° ; he = 0. 7hf , when a \( 90' ;where a is the included. angle between

two weld legs.

Figure 7. 1. 3 Sections of oblique-angle fillet weld

7. 1. 4 The strength of incomplete penetration butt weld (Fig. 7. 1. 4) shall

be calculated by ( 7. 1. 2 - 1 ) through ( 7. 1. 2 - 3 ) Formulas for fillet

welds, but using /If = 1. 0 , where the effective throat thickness shall be tak- I en as follows :

I

V -shape groove I I

w h e n a > 60°, he = s I

I when a < 60° , he = 0. 75s

U -shape and J -shape grooves he = s I

where s is the shortest distance from the root of groove to weld surface (ig- I I

noring weld reinforcement ) ; a is the angle of V -shape groove, ~

. ( I . ,., ..

Figure 7. 1. 4 Sections of incomplete penetration butt weld

a. b. c- V -shape groove ; d- U -shape groove ;

e- J -shape groove

When at the location of fusion line, the side length of weld section is equal to

or nearly equal to the shortest distance s (Fig. 7. 1. 4 b. c. e) , the design val-

ue of shear strength shall be taken as the design value of strength for fillet

weld multiplied by 0. 9. When the weld is subjected to the action of compression perpendicular to the

direction of weld length, the design value of its strength may be taken as that

for fillet weld multiplied by 1. 22.

7. 2 Bolted and riveted connections

I I

7. 2. 1 Ordinary bolts, anchor bolts and rivets shall be calculated according to

the following provisions:

1. In connections where ordinary bolts or rivets are loaded in shear, the de-

sign value of load-carrying capacity per ordinary bolt or rivet shall be taken

'as the lesser of the design values of shear capacity and bearing capacity:

Design value of shear capacity :

Ordinary bolt,

Rivet,

Design value of bearing capacity :

Ordinary bolt,

N : = d * E t e f i (7.2.1 - 3)

Rivet,

WE = do E t $, (7.2.1 - 4) where n, - number of shear planes;

d - diameter of bolt shank;

do - diameter of rivet hole ;

1 Zt - the lesser of the sum of the thicknesses of members stessed in

bearing in the same direction; --

fl, fb, - design values of shear and bearing strength, respictively , . of bolts ; .-

$, , $, - design values of shear and bearing strength, respectively,

of rivets.

2. In connectians where ordinary bolts, anchor bolts or rivets are loaded in

tension in the direction of their shank axes, the design value of load- carry-

ing capacity per ordinary bolt, anchor bolt or rivet shall be calculated by the

following formulas respectively:

Ordinary bolt,

Anchor bolt,

Rivet,

where d, - effective diameter at the threaded part of ordinary bolt or anchor

bolt ;

fi ,fl ,;E - design value of tensile strength for ordinary bolt, anchor - 60 -

bolt or rivet respectively.

3. Ordinary bolts or rivets, subjected to combined shear and tension (in the

direction of shank axes), shall meet the requirements in the following expres-

sions respectively : . .- .. . , i

Ordinary bolt,

Nv < N: Rivet ,

Nv \( N (7.2.1 - 11) where N u , N , - shear and tensile forces carried by each ordinary bolt or riv-

et ;

Nb, , N! - design values of shear, tension and bearing capacities

per ordinary bolt ;

AT:, N; , NE - design values of shear, tension and bearing capacities

per rivet.

7. 2. 2 High-strength bolts in friction-type joint shall be calculated accord-

ing to the following provisions :

1. In a shear resistant connection, the design value of load -carrying capaci-

ty per high- strength bolt in friction- type joint shall be calculated by the I

I

following formula :

(7:2. 2) . ' Nb, = 0 . 9nf ,u P where nf - number of load- transmitting friction interfaces ;

p - slip coefficient at friction surface, shall be taken as the value in

Table 7. 2. 2- 1 ; P - pretension per high - strength bolt, shall be determined in

accordance with Table 7. 2. 2 - 2.

2. In connections subject to tension in the direction of bolt axis, the design

value of capacity per high - strength bolt in friction - type joint shall be taken,

, . . . ...! . , . as N:. = .,O, .8PI .. ti . : . . .- . :.. . ;. ..,:.. :<, *,.". =+ ,f>.,72,. 2 q , .j., T,ci . ..,., . , 7:> . ,. ,

., ,"., . . ... " : . :, > . -,-..*.\ -' . ,$* 4

1- 3. When the high - strength bolted friction - type connection is subject to

shear between friction surfaces and external tension (in the direction of bolt

axis) simultaneously, the design value of shear capacity per high - strength

bolt in friction- type joint shall still be calculated by Formula (7. 2. 2 ) , but

I I P shall be replaced by (P - 1. 25N') . Here Nc is the external tension carried

by each high-strength bolt in the direction of bolt axis, and its value shall

not be greater than 0. 8 P .

Sand - blasting I

Slip coefficient at friction surface, ,u Table 7. 2. 2- 1

Treatment of faying surface

at the connnection of the member

Loose rust removed with wire brush ( 0.30 1 0.35 1 0.35 1 I

or untreated as-rolled clean surfaces

-- I

Pretension per high-strength bolt, P( kN ) Table 7. 2. 2-2 I

Grade 3 '

steel

Inorganic zinc-rich paint

coating after sand - blasting

Red - rusted after sand - blasting

7. 2. 3 High -strength bolts in bearing - type joint shall be calculated accord- ,

ing to the following provisions : - 62 -

16Mn steel

or 16Mnq steel

0. 35

0. 45

Property grade

of bolts

Grade 8. 8

Grade 1 0.9

15MnV steel

or 15MnVq steel

0. 40

0.55

Nominal diameter of bolt (mm)

0. 40

0. 55

M30

250

355

1 I

~

M16

7 0

100

M24

155

225

M 2 7

205

290

M20

110

155

M22

135

190

I 1. The pretension P and the treatment method of faying surfaces at the con-

nection of the member for high -strength bolts in bearing-type joint shall be 1 i

i the same as that for high-strength bolts in friction-type joint. 1 &. A- -, .+ -.-r High-strength bolts in bearing type joint are used only in connections of . - . .

~ structures subjected to static loading and indirect dynamic loading.

2. In shear resistant connections, the calculatihg method for the design value

of capacities per high-strength bolt in bearing-type joint is the same as that

for ordinary bolt, but the design value of shear capacity shall be calculated

with effective sectional area of the threaded part, when the shear plane passes

through the threaded part of the bolt.

I 3. In connections subjected to tension in the direction of bolt axis, the design

I value of tension capacity per high -strength bolt in bearing- type joint shall I

be taken as N! = 0.8P .

4. High -strength bolts in bearing- type joint subjected to combined shear

and tension (in the direction of bolt axis), shall meet the requirements of the

following expressions :

where N, ,Nt - shear and tensile forces carried by each high-strength bolt

in bearing- type joint ;

Nt , Ni , Nb, - design values of shear, tension and bearing capacities

per high - strength bolt in bearing- type joint

respectively.

5. In shear resisting connections and connections subjected to combined shear

and tension (in the direction of bolt axis), the design value of shear capacity

for high- strength bolt in bearing- type joint shall not be greater than 1. 3 times that calculated for bolt in friction- type joint.

7. 2. 4 At the end of a member to be co-mected in a joint or a splice, where

?. , 1 t t ::the ;connection :length l I between the centers of end bolts or rivets, measured

in the stressed direction, is more than 15d0 , the design values of capacities

?- for bolts or rivets shall be reduced by multiplying a reduction factor

11 (1 .1 - - 15 Odo

) . The reduction factor is 0. 7, when l l is larger than 60d0, do

I being the hole diameter.

7. 2. 5 In connections with the following situations, the number of bolts or

rivets shall be increased:

1. The number of bolts (exclusive of high-strength bolts in friction-type

joint) or rivets connecting one member to another with fillers or other pack-

ing plates shall be increased by 10% above the number calculated in accor-

dance with Clause 7. 2. I.

2. The number of bolts (exclusive of high-strength bolts in friction - type

joint) or rivets in a lap joint or a joint with single splicing plate shall be in-

creased by 10% above the number calculated in accordance with Clause I

7. 2. 1.

3. When lug angles are used in end connections of members to connect the I

outstands of their angle or channel sections in order to reduce the connection

length, the number of bolts or rivets used in one of the two legs of the lug an- I

gle shall be increased by 50% more than the number required by calculation.

47 Where the grip length of a rivet exceeds 5 times the hole -diameter, the

number of rivets required by calculation shall be increased by 1% for each L

additional 2 mm of grip (not less than 1 rivet), but the grip of a rivet shall

not be greater than 7 times the hole diameter. r. - 64 -

7. 3 Flange connection of builtup I-girder.

: 7. 3. 1 The strength of fillet welds connecting the flange to web of a builtup I . . . . . . ' . , .,.- r . r -rr. L* L C .

.: < . . . * . ; . , ). .,.&'g;r&&"&ii bdt,h Ad& ..kh.&i be cdlEul&!&a b$ 'the yoli&*:i&k- f~~&m~rg::. .r?&,i:i:ii I

where S1 - static moment of gross section of the flange about neutral axis of

the girder;

I - Moment of inertia of gross section of the girder. 1 F , $ and lz shall be used in accordance with Clause 4. 1. 3 , and flf in accor-

dance with Clanse 7. 1. 2. -Votes : 1 . where& the t o p flange o f the girder is subject to fixed concent~atsd loads, bearing stif f w s

should be provided wiUI Uleir ends closely fiUed to the top flange. In this case,put F = 0 . 2. The strength of welds may not be calmlated provided the flange to w b w n ~ e ~ t h is made b.J com-

plete penetration buff weld.

7. 3. 2 The capacity of rivets (or high - strength bolts in friction - type

joint ) connecting the flange to web of a built-up I -girder shall be calculat-

ed by the following formula:

where a - spacings of flange rivets (or bolts) ;

al - coefficient: in case the load F acts on the top flange of the

girder and its web is planed and fitted closely to the top flange

plate, al = 0. 4 ;in other cases, al = 1. 0 ; x,i, - the lesser of design values of .shear capacity and bearing

capacity per rivet ;

I?! - the design value of shear capacity per high-strength bolt in

friction - type joint. -. , * -

:Vote: See note 1 in Clause 7 . 3. 1 .

7. 4 Supports (Bearings)

7. 4. 1 The bearing stress of he cylindrical pin in a hinged pin support

(Fig. 7. 4. I ) , with a central angle of the contact surface 90' , shall be

calculated by the following formula :

where R - reaction of support;

d - diameter of pin.; '.

r

1 - longitudinal length of the contact surface of the pin.

7. 4. 2 The bearing stress for the free contact between a curved bearing plate

I and a flat plate (Fig. 7. 4. 2)shaU be calculated by the following formula:

where r - radius of the curved surface of bearing plate;

l - length of contact line between curved surface and flat plate.

Figure 7. 4. 1 Hinged pin type support

Figure 7. 4. 2 Curved plate support

7. 4. 3 The bearing stress for free contact between rollers and flat plates shall

be calculated by the following formular:

where n - number of rollers j - 66 -

dl - diameter of roller ;

I - length of contact line between roller and flat plate.

Figure 7. 4. 3 Roller support

7. 4. 4 Provided the end surface of an axially loaded compression column or a

.beam - column is machined flush, the maximum compreesive force in the

column will be transmitted directly through contact between the machined

abutting end faces, the connecting welds ,rivet or bolts shall be calculated ac-

cording to 15 % of the maximum compressive force ;when a tensile zone oc-

curs at the end of a beam-column, the connection at this tensile zone shall

be also calculated according to the maximum tensile force.

8 Requirements for Detailing

8. 1 General requirements

8. 1. 1 The details of steel structures shall be so designed as to facilitate the

fabrication, erection and maintenance, and to make the structure stressed

simply and definitely with less stress concentration. For open web structures

in which wind load predominates, efforts shall be made to reduce the area

facing the wind.

8. 1. 2 For load- carrying members and their connections of steel structures,

the following materials should not be used: steel plate with thickness less than

5 mrn; steel tubes with wall thickness less than 3 mm; steel angles with sec-

tions smaller than L45x4 or L56x36x4 (for welded structures ) or smaller '

than L5 0x5 (for bolted or riveted structures), However, light steel structures

described in chapter 11 are not subject to such limitations. I

I 8, 1. 3 Whether or not it necessary to take such special measures as pre-heat

ar post -weld heat treatment for welded structures shall depend upon the I

I combined factors of the property of steel, the thickness of parts to be welded,

welding process, the ambient temperature during welding, etc. Under normal I

conditions, the thickness of the parts to be welded should be not thicker than

5 0 mm for low - carbon steels, and not thicker than 36 mm for low -alloy I

I I

steels.

8. 1. 4 In order to ensure the spatial performance of structures, to increase

their *overall stiffness,' to carry and transmit horizontal forces, to pfe'veiit the hb"

members from excessive vibration, to avoid the lateral buckling of compres-

sion members, and to ensure the stability of structures during erection, reli-

able bracing systems shall be provided according to the different conditions of - 68 -

structures and loadings. Separate independent and spatial - stable bracing

systems shall be provided in each section between expansion joints or each

section for construction by stages.

. - . * - - 8. 1. 5 The temperature stress may not be calculated when the length of the

section between expansion joints (the distance between expansion joints) for .- single -storey buildings and out - door structures does not exceed the values

given in Table 8. 1. 5.

1 joints shpll be provided in accordance udh provisMls in correspending Codes. I

Length of section between expansion joints (m) Table 8. 1. 5

For cladding stTuctu~es, expansion joints m y be provided separately according to the specific &-

cu~nslonces and r e f w i n g to relevant codes.

2. Inter-colu~nn bracings (bracings between columns) in the buildings without overhead tTaveUing mane, and

Situations of

structures

Buildings with heating and

buildings in regions

without heating Hot workshop and

buildings without heatixlg

in regions with heating

open air structures

inter- column bracings below the mane girders or crane trusses in buildings with overhead traveUing mane

should be arranged symmetrically in the middls part of the section between expansion joints. When inter-

-1btes: 1. When the columns in an industrial building m e made from materials other than steel, expansion

Longitudinal

section between

expansion joints

(norm& to the

direction of truss

or frame span

220 .

180

120

Transverse section

between expansion joints

(a l~ng the direction of

truss of frame span)

coluinn bracings m e arranged nonspnmetrkaUy, the distance from the mid point of the above metwned brac-

Rigid joint at

top of column

120

100

-

i n g ~ ( from the mid point of the two sets-of bradngs i f t ~ , sets of bracings m e to be arranged) to the ends -9

of the section betuven ezpansion joints should not be greater than 60% of the length of longitudinal sectibn

Hinged joint at

top of column

150

125

-

between expansion joints given in Tabb 8. 1. 5.

1 8. 2 Welded connections

- 69 -

8. 2. 1 The weld metal should match the base metal. When steels having dif-

ferent strength are to be connected, the weld materials matching the steel of

lower strength may be used.

.- 8. 2. 2 In the design, the weld size and length shall not be increased arbitrari-

ly, the three-dimensional intersection of welds as well as the concentration

of a large number of welds at one location should be avoided, and the welds

should be arranged as symmetrically as possible with respect to the centroid of 1 j the members. I

I

,\-ole :For splice steel plates when butt welds aTe used, the longitudinal and t~ansverse butt welds may intersect

to form a squaTe cr05sitig 'o~-a-?Z'- juircEionl'wh'~\T- j&ctiW a ~ e ymmed ,the distance between inter- & ~ .~GJ~ ,Z~ : r; secting points shall not be less than 200mm.

8. 2. 3 The type of grooves for butt welds shall be selected on the basis of the

plate thickness and constructuin conditions, according to the requirements of

the current standards, Basic type and size for welded connection with manu-

al arc weldingt' and Basic type and size for welded connection with sub-

merged arc welding".

.- Fig. 8. 2. 4 Splice of steel plates with different widths or thicknesses

a - different widths ; b - Different thicknesses

I 1 8. 2 - 4 At the splice joined with butt welds, when the parts to br welded have

I

different widths or their thicknesses differ more than 4 mm, a transition in I

"-2 * width or in thickness j withaalope not~lateeper 8hm 1 in -4 on one side or both *,Z%~U+K

sides ; shall be made (Fig. 8. 2. 4 ) . When their thicknesses are different, the type of weld grooves shall be

selected on the basis of the thickness of the thinner part welded in accordance

with the requirement in Clause 8. 2. 3.

8. 2. 5 Where incomplete penetration butt welds are used, the type and size

of grooves shall be noted on the design drawings, the effective thickness he

(mm) of welds shall not be less than 1. 5 f i , where t is the greater thick-

ness (mm) of the welded parts. I

In structures subject to dynamic loadings, incomplete penetration butt welds

should not be used for welds perpendicular to the direction of applied force.

8. 2. 6 The included angle a between the two legs of a fillet weld is generally

9 0' (right angle fillet weld) oblique -angle fillet weld with angle a > 12 O0 or

a < 60° , should mot be used as load-carrying welds (except in steel tubu-

lar stractures) . 8. 2. 7 The size of the fillet welds shall comply with the following require-

ments :

1. The leg size of fillet welds hf (mm) shall not be less than 1. 5 2/ t where t

I .

1 is thickness of thicker part welded (mm) . However, for automatic welding,

I the minimum leg size may be reduced by 1 mm;for single side fillet weld in T I

i joint, it shall be increased by 1 mm, If the thickness of welded parts is equal . . . .

I t'o or less than 4 mm, then the minimum leg size shall be the same as the . ;' ..%' . 'i ;. :PI .- -tbidkn& 6.f ;.'virk-lded Pi8~.'t. , (":? ' r ; . :<:. - - ;'$&.@).):* r;v~c&; c . .,m i:>ci , ; i ~ < . ..; .,>- 3 ;$-+.. ' : >:~~>; t .r:-,. -.'. -*c I > . - .. . ' , . . .-, .: % %

!

1 - 2. The leg size of fillet welds should not be larger than 1. 2 times the thick- .-

I ness of the thinner part welded (except in steel tubular structures) , but the I

I maximum leg size of fillet welds along the edege of welded part (thickness be-

ing t ) , shall also comply with the following requirements :

The leg size of fillet welds in circular holes or slotted holes should also not be

larger than one third of the diameter of the circular hole or the short diameter

of the slotted hole.

3. The fillet welds are generally made with equal leg sizes. When the differ-

ence in thickness of the parts to be welded i? comparatively large, and the e-

qual leg sizes can not meet the requirements specified in Item l and 2 of this

Clause, the fiilet welds with unequal leg sizes may be used, the leg contacting

the thinner part shall comply with the requirements in Item 2 of this Clause,

and the leg contacting the thicker part shall comply with the reqiurement in

Item 1 of this Clause. I

4. The effective length of a side fillet weld or a transvers fillet weld shall be \ I 1 not less than 8hf nor less than 40mm.

5. The effective length of a side fillet weld should not be larger than 60 hf

(when subjected to static loading or indirect dynamic loading) , or 4 0hf (when

subjected to dynamic loading) ; When in the effective length exceeds the val-

ues stated above, the excess portion will not be taken into account in calcula- I

tion. This limitation is not applicable if the internal force is uniformly dis- I I

tributed along the whole length of a side fillet weld. I

8. 2. 8 In structures subjected to direct dynamic loading, the surface of fillet

welds shall bo made flat or concave. The ratio of leg sizes should be 1 : 1. 5

for transverse fillet welds (the longer leg parallel to the direction of internal

I

I force) , but may be 1 : 1 for side fillet welds.

8. 2. 9 h secondary members or secondary welded connections, intermittent

i - fillet welds may be used. The clear unconnected gap between the ends of the i 1 . @ ~:i-,:l welds-shall not .be +more than 15t (for members in compression) or* 3Ot :(for ,

members in tension), t being the thickness of the thinner part welded. .-

8. 2. 10 When the end of a plate element is connected by two side fillet welds

only, the length of either fillet weld should not be less than the distance be-

tween the two side fillet welds; and ,at the same time, this distance should be I not larger than 16t (for t >12mm) ,or 200mm(for t <12mm), t being the

thickness of the thinner part welded.

8. 2. 11 h the connection of a member to a gusset plate ,fillet weldson two

sides of member should generally be used and fillet welds on threeside may al-

so be used. Steel angle members may use L - shape fillet welds. The fillet

welds must be continous aroundthe corner for all the round weldings.

a. Welding on two sides ; b. welding on three sides ; c. L-shape welding

Fig. 8. 2. 11 Welded connection of a member to gusset plate

- -

8. 2. 12 Wherever at the corner of a member end, the fillet weld is returned

around the corner for a length 2hf , the fillet weld must be continuously

aro-md the corner. . . &. - . . - . ,-.. -- --..~..-.-._.---_---...-.....-,... ._.C-. -* .- -- . . ." __ - 1. -_ . ---.- i -- _ . -. .-.- ._.----.-- _.--

. - 8. 2. 13 The amount of lap in a lap connection shall be not less than 5 times

the thickness of the thiner part welded, nor less than 25 rnm.

8. 3 Bolted and rivet connections

8. 3. 1 The number of permantent bolts( or rivets) used at the end of each .* . ..* % .member to be connected in a joint or a splice should riot be less than two. For

built-up laced members, one bolt (or rivet) may be used at the end connec-

tion of lacing bar.

8. 3. 2 Holes for high strength bolts shall be drilled, Diameter of holes for

high -strength bolts in friction type joint should be 1. 5 - 2. Omm larger than

the nominal diameter, d , of the bolt. Diameter of holes for high-strength

bolts in bearing type joint should be 1. 0 - 1. 5mm larger than the nominal di-

ameter, d , of the bolts.

8. 3. 3 The method of treatment for faying surfaces of the members in a high

-strength bolts bolted connection shall be noted in construction drawings.

8. 3. 4 The allowable distance of bolts and rivets shall comply with the re-

quirements given in Table 8. 3. 4,

Maximum and minimum allowable distance of bolts and rivets

Table 8. 3. 4

-Votes: 1. do is hole diameter o f bolts a rivets, t , i s thickness of thinner outside part connected.

Name

Distance

between

centers

Distance

from center

to edge

to end

of a member

2. The maximum spaoing of bolts or Tivets on the rau adjacent to the edge o f plote connecting to a

~ i g i d member (e . g. angk , channel ,etc. )may be token as that specified f o ~ inner TOW.

8. 3. 5 Grade C bolts should be used in connections subject to tension along

the direction of bolt axis ,and may be used in connections subject to shear for

the following cases :

1. Secondary connections in structures subject to static loading or in-

direct dynamic loading.

2, Connections in detachable structures not subject to dynamic load-

ing.

3. The erection connections for temporay fixing of members.

Location and direction

8. 3. 6 For ordinary bolted connections subject to direct dynamic loading,

double nuts or other effective measures to prevent loosening of nuts shall be

taken.

8. 3. 7 When members made from rolled steel shapes are to be spliced by high

-strength bolts, the steel plates should be used as splicing materials. - 75 -

maximum allowable

distance(whichever

is the lesser)

8do or 12t

12d0 or 18t

l6d0 or 24t

.

4do or 8t .- .,.*-- ." ,. .

Ln any

direction

Minimum

allowable

diatance

do

2do

1. 5d0

1. 2d0

Outer row

inner

row

Along the direction of internal force

member in

compression

member in

tension

perpendi-

cular to the

direction

of internal

force

Cut -edge

Rolled

edge

High -strength

,. ., bolt- . . Ordinary bolts

or rivet

8. 3. 8 Rivets with countersunk heads or semi-countersunk heads shall not

be used in connections subject to tension along the direction of the rivet axes.

8. 4 Structural members

(I) Columns

8. 4. 1 Lacing bars should be used for built-up open ewb columns with com-

paratively large shear force or comparatively large column width in the lacing

planes. The sum of the linear stiffnesses of the batten plates (or traverse . bars made from rolled steel shapes) at the same cross section in a battened

nent of the column.

8. 4. 2 When the ratio of the effective depth, ho , to the thickness, t, , of the

web in solid web columns is greater than 80, the web shall be strengthened

with transverse stiffeners, for which the spacing shall not be larger than 3ho.

The dimension and details of the transverse stiffener shall be designed in

accordance with the relevant requirements in Clause 4. 3. 7.

8; 4. 3 Transverse diaphragms shall be provided at locations of comparatively

large horizontal forces and at the ends of each shipping unit in laced or bat-

tened columns or large size solid web columns. The distance between the di-

aphragms shall be not more than 9 times the larger width of column section,

nor 8 m.

(11) Trusses - ,.,.. ,.

8. 4. 4 In welded trusses, the axes shall be taken as the centroidal lines of the

members, and in bolt (or riveted) trusses, the axes may be taken as the - 76 -

gauge lines of bolts (or rivets) adjacent to the centroidal lines of the mem-

bers. At a panel point (joint) , the axes of the relevant members shall inter-

sect at one point.

In case that the chord member of a truss changes in cross section, and

the eccentricity due to such change does not exceed 5% of the height of the

larger chord section, the influence of eccentricity may not be considered.

.- 8. 4. 5 In stress analysis of a truss, all joints of the truss may be regarded as

hinged. When the members are made from H -section, box - section, etc.

With comparatively large stiffnesses, and also the ratio of the height of mem-

ber section to the geometrical length (distance between centers of joints) is 1

larger than 1/10 (for the chord member) or larger than 1/15 (for the web

member.)+the secondary moment induced by the joint rigidity shall be-taken , ,-;:, ;

into account.

8. 4. 6 When the members of a truss are connected with gusset plates, the gap

between the chord and the web members, or between the web members them-

selves should not be less than 20 rnm. I I I

I 8. 4. 7 The thickness of the gusset plate is generally determined according to

the magnitude of the internal forces in members connected, but shall not be

less than 6 mm. The errors in fabrication and assembly shall be properly tak- I en into account in determining the overall dimensions of the gusset plate.

I

8. 4. 8 For trusses with spans greater than 36 m and hinge-supported at both

ends, under the action of vertical loading, the influence of the horizontal

thrust due to elastic elongation of the bottom chord on the supporting mem-

bers shall be taken into account.

8. 4. 9 Simply supported triangular trusses of 15 m or greater span, and sim-

ply supported trapezoid or parallel - chord trusses of 24 m or greater span 1

may be cambered with an amount of about -th of the span, when the bot- 500

tom chord is not curved or bent.

(111) Beams

, - -

8.-4. 10 The flange of welded be- is generally made from one plate. When

two plates are used, the ratio of the thickness of the outer plate to that of the

inner one should be 0. 5-1. 0. In case that the outer plate does not extend

the whole length of the beam, the length of the extended portion, Z1 , beyond

the theoretical cut - off point shall comply with the following requirements :

With transverse fillet weld across the end

When h2 0. 75t I1 2 b

When h< 0. 75t 1, 2 1. 5b . i

Without transverse fillet weld across the end

z, 2 2b where b and t are the width and the thickness of the outer flange plate

respectively; hf is the leg size of the side and the transverse fillet weld.

8. 4. 11 The numberof flange cover plates of riveted (or high -strength bolt-

ed in friction type joint) girders should not be more than 3 , the area of the

flange angles should not be less than 30% of the total flange area. If this re-

quirement still can not be satisfied even by using the largest angle sections,

side plates may be added (Fig. 8. 4. 11) . In this case, the sum of the areas I

of angles and side plates shall not be less than 30% of the total flange area.

In case that a cover plate does not extend the full length of the girder,

the number of rivets ( or high-strength bolts in friction- type joint) in the

extended portion beyond the theoritical cut - off point shall be determined ac-

cording to the capacity of 1 / 2 of the net sectional area of this plate.

8. 4. 12 The transverse stiffeners of a welded girder shall be corner-cut at

their ends meeting under side of the flange. When the corner - cut is

oblique, the width of clearance is about b,/3 (but not larger than 40 rnrn) , and the height of clearance is about b,/2 (but not larger than 60 mm) as

- 78 -

shown in Figure 8. 4. 12, where b, is the width of stiffener.

Fig. 8. 4. 1 1 Flange section of Fig. 8. 4. 12 Corner-cut of

riveted (or high -strength bolted stiffeners

in friction type joint)girder I , j I j

8. 4. 13 When the bottom end of bearing stiffeners at beam supports is calcu- I

lated according to the design value of end bearing streng*, the bottom end ~ shall be planed and closely fitted, and, in addition, the length of the extend-

ed portion of flanged bearing stiffeners (Fig. 8. 4. 13b) shall not exceed twice I

the thickness of the stiffener.

I

I

planed

closely fitted

planed

colsely fitted

Fig 8. 4. 13 Support of beam

(IV) Anchor bolts of column bases

8. 4. 1 4 The anchor bolt of a column base shall not be used to carry the hori- I

zontal reaction at the bottom of column base, this horizontal reaction shall be

carried by the friction force between base plate and concrete foundation or by

the shear - resistant key provided. - I

i

8. 4. 15 The anchor bolts of a column base shall be embedded in the founda-

tion with a depth sufficient to transmit the tensile force in the anchor bolt

through the bond betwwen bolt and concrete. If the embedment depth is lim-

ited, yhen the anchor shall be securely fixed to an anchor plate or anchor

beam embedded in the foundation to transmit all the tensile force of the an- chor bolt. In this case, the bond between anchor bolt and concrete may be ig-

nored.

8. 5 Requiements for crane girders and crane trusses (or similar gird-

- 80 -

ers and trusses

8. 5. 1 The flange of welded crane girder should be made from one plate. If

two plates are used, the outer plate should extend the full length of the gird,

e r , and measures shall be taken in .design and construction so that the two I plates of the top flange will be in close contact. I

I

I

8. 5. 2 Crane truss and surge truss should not be used, for structures support-

ing soaking pit crane, stripper crane or rigid-claw crane as well as similar ,

cranes.

I I, 8. 5. 3 The welded crane truss shall comply with the following requirements:

1. At the joint of truss, the gap, a , between a web members and the - 1 chord member should not be less than 50 mm, and the two edges of

the gusset plate should be rounded with a radius, r , not less 'than 60

mm. the angle, 0 , between the axis of the web member and the edge . I

of gusset plate shall not be less than 30°(Fig. 8. 5. 3). The start or I

stop of arc of the weld-run in a weld connecting the chord member

of angle sections to the gusset plate shall be set back at least 5 mm I

(Fig. 8. 5. 3a) from plate edges. The weld in T connection connect-

ing the gusset plate to the I-section chord member shall be fully pen-

etrated, the rounded portion of the gusset shall be free from defects

due to start - stop of weld - run, and further more, for the crane

truss for heavy duty cranes, the rounded portion should be ground to

make a smooth transition from the gusset to the chord member.

2. When fillers in a member are connected by welding, the start or stop

of weld- r;n shall be set back at least 5 mm (Fig. 8. 5. 3c). The

fillers in members of a crane truss for heavy duty cranes shall be con-

nected by high-strength bolts.

- 81 -

Fig. 8. 5. 3 Joint of crane truss

8. 5. 4 The complete penetration butt weld performed with the aid of run-on

stabs shall be used for welded splice of the flange or the web in a crane gird-

er , and shall be ground flush at locations where the run-on stabs are cut

off. The high-strength bolted friction- type connection should be used for

the field splice of fabricated segments of a crane girder.

8. 5. 5 In welded crane girder or crane truss, the weld in a T- connection in

the following locations shall be fully penetrated with weld quality not lower

than the second class weld standard (its shapes as shown in Fig. 8. 5. 5) :

Figure 8. 5. 5 Complete penetration weld in T connection

1. The web to top flange connection of crane girders for heavy ddty I

cranes and for medium duty cranes with lifting capacity Q 2 5 0 t .

2. The connection of the gusset plates to the top chord of crane truss$.

8. 5. 6 The top end of the transerse stiffener of a crane girder shall be planpd

and closely fitted against the top flange (and also should be welded to it ;in

case of a welded crane girder). The bottom end of the intermediate t rd s - --

verse stiffener should be cut off at 50- 100 & from the inner face of tefi-

sion flange and shall not be welded to the tension flange by using any ad - Q tional parts. During the performance of the weld connecting the intermediqte

transverse stiffener to the web, there should be no start or stop of weldYrjn I

at the bottom end of the stiffener. \ 1

When bracings are connected to the tension flange of a crane girdet, I

welding should not be used. I

8. 5. 7 The requirements for detailing of the top chord of a crane truss i$n I

which rails are placed directly, shall be the same as those for the crane gird-

8. 5. 8 In crane girder for heavy duty cranes, high-strength bolts in fricti4n I

-type joint should be used for the connection of the top flange to the sur$e

structure as well as for the connection transmitting horizontal forces to the

column. I I

The details for the connection of the ends of a crane girder to the colurrjn

shall be so designed.as to minimize the additional stresses at the connectidn

due to the flexural deformation of the crane girder.

8. 5. 9 When the span of a crane truss or a crane girder for heavy duty cran fs is equal to or greater than 12 m, or the span of a crane girder for light and

I

medium duty cranes is equal to or greater than 18 m, auxiliary truss and hof-

izontal bracing system should be provided. The vertical bracings, when thdy I

are provided, should not be located at the point of maximum vertical defleq- I

tion of crane girder or crane truss. I I - 83 - I

The measures in detailing for crane truss shall be taken to prevent its top

chord member from torsion due to the eccentricity of rails. <A,.

8. 5. 1 0 The edges of the tension flange plate of a crane girder for heavy duty

cranes (or the tension chord member of a crane truss) should use the auto- = matic precise flame cutting, and shall be planed along its full length when

I- manual flame cutting or shear cutting used.

8. 5. 11 Attachments for hanging appliances shall not be welded to the tension ,

flange of a crane girder (or the tension chord of ,a crane truss), and striking . 4

I arc or welding of clamps should not be done on the tension flange.

8. 5. 12 The joint details of crane rail shall be designed to ensure smooth and

steady passage of crane wheels. When welded long rails are used and fastened

to the crane girder with clamp plates, the contact between the clamp plates

and the rail shall not be too close, so that longitudinal-expansion and contrac-

tion of rail due to temperature variation will be possible.

8. 6 Fabrication, transportation and erection

8. 6. 1 In dividing a structure into units for trasportation, beside that the

stress condition of. the structure shall be considered, attention shall also be . ' +.. ,. ."i .. 'i

I

paid to economic rationality, convenience of trasportation and ease of assem-

bly.

8. 6. 2 For erection connections of a structure, such types of details that en-

sure reliable transfer of forces, convenience in fabrication, simple connec-

tions and ease of adjustment, shall be used.

8. 6. 3 When welded connections are used for erection, provision of position-

ing bolts for temporary fixing of members shall be considered.

- 81 -

8. 7 Corrosionprotection and heat isolation

8. 7. 1 For steel structures, beside that measures (painting and galvanizing

after thorough removal of rusts, etc. ) for protection against corrosion must

be made, constructional details shall be designed to avoid, as much as possi- I , -

ble, places difficult of inspection, cleaning and painting, dead spaces or

.- grooves where moisture and lot of dust can accumulate. The closed-section 1 member shall be sealed by welding, along its full length and at the ends. 1

Except for special needs, generally, there shall be no extra increase in

section or thickness of steel in the design to take account of corrosion.

) 8. 7. 2 The portion below ground level of a column base, shall be encased

with concrete of lower strength (the thickness of concrete cover shall not be

less than 50 mm) , and the encasing concrete shall be about 150 mm above I I

the ground level. When the bottom of the column base is above the ground

level, the bottom of column base shall be not less than 100 mm above the

ground level. I

I

8. 7. 3 For structures subjected to the action of corrosive medium and parts of

structures inaccessible for repainting during service r special provisions (mea-

sures) for protection against corrosion shall be made. The column base sub-

jected to the action of corrosive medium should not be embeded in the 1 ground.

8. 7. 4 For structures subjected to the action of high temperature, the follow-

ing protective measures shall be taken according to different situations:

1. When a structure may be subjected to the attack of red-hot molten

metal, it shall,& protected by using heat insulation cover made from

bricks or heat resistant materials.

2. When the surface of a structure is subjected to the action of long-

time radiant heat above 150°C , or subjected to the possible action of

flanie in a short time, the effective measures for protection shall be , - 85 -

I

provided (e. g. providing a heat isolation cover or water jacket, I

etc. >. I

9. Plastic design

9. 1 General requirements

9; 1. 1 The provisions in this chapter apply to the design of built-in end

beams, continuous beams, one- and two- story rigid frames with solid web

members when they are not subject to direct dynamic loads.

9. 1. 2 For plastic design of steel structures or members according to the uti-

mate limit state, the design value of loads shall be used. Considering the de-

velopment of plastisity within the section of members and the redistribution of

internal forces thus induced, the simple plastic theory is used for structural

analysis.

For design according to the serviceability limit state the charateristic val-

ue of loads shall be used, and calculations are based on the elastic theory.

9. 1. 3 The design values of strength of steel and connections specified in

Clause .3. 2. 1 and Clause 3. 2.2 shall be multiplied by the reduction factor of

0. .9 for plastic design according to the provisions in this' chapter. F

9. 1. 4 For plastic design, the width- to- thickness ratio of the plate ele-

ments of sections shall meet the requirements in Table 9. 1. 4.

width-to-thickness ratio of plate elements I

I T y p otssection 1 Flange

Table 9. 1. 4

Web

N When- < 0 .37 , Af

N When - 2 0 . 3 7 , Af

Same as that for the web of

I-section shown above

A70te: N - aziul compressive force in the member;

A - gross cross- sec t iod area;

f - design value o f steel strength in tension, compression a d bending for plostic design, see Cluuse

9.1. 3.

9. 2 Calculation of members

I

9. 2. 1 The bending strength of flexural members subject to bending moment

Mx in one of the principal planes of the section ( for I - sections, x-axis

being the strong axis) shall satisfy the following requirement: 1

where W , - net plastic section modulus with respect to the x-axis.

9. 2. 2 The shear force V of the flexural member is assumed to be carried by

the web of the section. The shear strength shall satisfy the following require-

ments :

where h,,, , tw - the depth and thickness of the web, respectively ; - 88 -

f, - design value of steel strength in shear for plastic design, see Clause

9. 1. 3. I

9. 2. 3 The strength of beam-columns subject to bending moment in one of

the principal planes of the section shall meet the requirements of the following,- .- . _ , . ." formulas :

N when - < 0.13,

Rf

N when - > 0.13,

Rf

where R - net cross-sectional area.

The compressive force, N , of the beam-column shall not be greater than

0. 6 4 f , and the shear strength shall meet the requirement of Folm~.~la(g. 2.

9. 2. 4 The stability of a beam-column subject to bending moment in one of I

the principal planes of the section shall meet the requirements of the following

formulas :

I. In-plane stability of a member

where W, - gross plastic section modulus with respect to the x-axis. pz , I

NErand j3, shall be taken in accordance with Clause 5. 2. 2 for calculation of

..

the in-pla& stability.

2. Out-of-plane stability of a member

, " N . . - - -v -+ B1Mz < 1 (9.2.4 - 2) %Af g>aFtT,f

Q , ~ , and &shall be taken in accordance with Clause 5.2.2 for calculation of

the out - of -plane stability.

9. 3 Allowable slenderness ratio and detailing requirements

I

9. 3. 1 The slenderness ratio of compression members should not be greater

9. 3. 2 Members must be laterally braced at the plastic hinge locations. The

slenderness ratio, h, , of the member between such braced location and its ad-

jacent laterally braced points shall meet the following requirements:

M1 When - 1 < - w,f < 0- 5 9

M1 When 0.5 < - w f < 1. 0,

11 where4 = T- - out - of - plane slenderness ratio, ZI being the distance be- 2,

tween adjacent laterally braced points and i, being the radius

of gyration of the member section about the weak axis.

MI - bending moment at the laterally braced point distant Zl from the plastic - 90 -

MI hinge section, - is positive when the segment with length ll is bent in WPf

single curvature, and negative when bent in reverse curvature.

In regions where no plactic hinges occur, the distance between two I

points of lateral support shall be determined by checking the overall out-of

- plane stability of the member according to the relative provisions .in Chap- a

ter 4 and Chapter 5.

9. 3. 3 The axial force in the lateral bracing used to reduce the out --of - plane effective length of the member shall be determined according to Clause

4. 2. 5 or Clause 5. 2. 8.

1

9. 3. 4 All the joints and their connqtions shall prwess sufficient rigidity to

ensure the angles between members meeting at the joint to be unchanged be-

fore the appearance of plastic hinges.

The splice and connection of the member shall be able to transfer 1. 1

tinies the maximum computed bending moment at these locations. The mo- ment capacity at these locations shall not be less than 0. 25WPf.

9. 3. 5 If the edges of plate elements are cut by manual flame-cutting or

shearing machine, the edge at plastic hinge location shall be finished smooth

by planing.

Bolt holes on tensile plate elements at plastic hinge locations of a member

shall be drilled full size or sub-punched and reamed.

4

f

1 0. Steel 'tubular structures

10. 0. 1 The provisions .in this chapter apply to circular pipe structures with D

directly welded joints and not subject to direct dynamic loads. - s.

C 10. 0. 2 The ratio of outside diameter to wall thickness of steel pipe shall not

235 exceed 1 0 0 [-I .

f,

10. 0. 3 The detailing of steel pipe joints shall meet the following require-

ments : I 1

1. The outside diameter of the main pipe shall be larger than that of the sub I -pipe, and the wall thickness of the m& pipe shall not be thinner than that

of the sub - pipe. The sub- pipe shall not penetrate into the main pipe at

their connections.

2. The angle 0 between the axes of the main pipe and sub- pipe or between

the axes of two sub- pipes should not be less than 30'. 3. Eccentricity shall be avoided as far as possible at the joints connecting the

sub-pipe to the main pipe.

4. The weld connecting the sub-pipe to the main pipe shall be continuous

around the perimeter of the sub -pipe and made with a smooth transition to

the base metal.

5. The end of sub - pipe should be cut by the automatic pipe cutting ma-

chine, and the end should not be grooved if the wall thickness of the sub-

pipe is less than 6 mm. 10. 0. 4 Steel pipe members shall be reinforced by appropriate measures at lo-

cations of relatively large transverse loads to prevent the occurance of exces-

sive local deformations.

Holes shall be avoided at major stressed locations of the steel pipe member. If holes at there are necessary, appropriate measures of strengthening shall be

taken.

10. 0. 5 In the connection of a sub-pipe with a main pipe, fillet weld may

be used around the perimeter of the sub- pipe, or part fillet weld and part

butt weld may be used. In the region where the angle between the walls of

sub-pipe and main pipe exceeds or be equal to 120°, the butt weld or the

grooved fillet weld may be used. The leg size of fillet weld should not be - .

I ,- greater than twice the wall thickness of the sub-pipe to be connected.

10. 0. 6 The weld connecting a sub-pipe to a main pipe may be assumed as

a fillet weld around all the perimeter of the sub-pipe and calculated accord-

ing to Formula 7. 1. 2 - 1 , but taking f l f = 1 . The effective thickness of the

fillet weld is variable around the perimeter of sub-pipe, 0. 7hf may be taken

as the average effective thickness when the sub- pipe is axially loaded. The

effective length of the weld, the length of intersecting curve, may be calcu-

lated according to the following formulas :

d, when -<0. 65, d'

I,= (3.25dS- 0.025d) C- 534 +O. 4661 sine ( lo . 0.6-1) I

d, when d>O. 65,

534 + 0.4661 I,= ( 3 . 8 1 4 - 0.389d) [- sine

where a , a8 - outside diameters of main pipe and sub- pipe, respectively ; 1 I

0 - angle between the axes of main pipe and sub-pipe.

1 0. 0. 7 To ensure the strength of the main pipe at joints, the axial force of

the sub-pipe shall not be greater than the design value of capacity calculated

according to the following requirements :

Fig. 10. 0. 7

a. X joint b.

Types of joints

and Y joint c. K joint

1. X joint (Fig. 10. 0. 7a)

1) The design value of capacity, NcpJ , of the sub - pipe in compression at

joints shall be calculated by the following formula:

where /? = - " - ratio of outside diameter of sub-pipe to that of the main d

o Yn - parameter: Yn = 1 + 0. 3 - - 0. 3[Zl2 when o < 0,

f v f v

Kt =1 when o > 0; t - wall thickness of the main pipe;

f - design value of steel strength in tension, compression and bend-

ing; a -maximurn axial stress in main pipe (tensile stress taken as posi-

tive, compressive stress as negative).

2 ) The design value of capacity, Ntj , of sub- pipe in tension at joints shall

be calculated by the following formula: - 94 -

Ntj = 1. 5Ngj

2. T joint and Y joint (Fig. 10. 0. 7b)

1 ) The design value of capacity, Ngj , of the sub - pipe in compression at - joints shall be calculated by the following formula,

I -r where Yd - parameter, taken as

1 Yd = 0. 069 + 0. 938 when /? < 0. 7 I

Yd = 28- 0. 68 when /?> 0.7 I

I 2) The design value of capacity, Nfj , of sub - pipe in tension at joints shall

I

I be calculated by the following formula: ,

I I when 8 < 0.6 ,

N? = 1.4N:j

when@ > 0.6 , Nlj = (2 - /?)NP'

3. K joint (Fig. 10. 0 . 7 ~ )

1) The design value of capacity, Nzj , .of sub-pipe in compression at joints I - shall be calculated by following formula: I

I where 8, - angle between the axis of sub-pipe in compression and axis of I

I I main pipe ; I

I Ya - parameter, calculated by the following formula: I

I a - gap between two sub - pipe, taking a = 0 whena < 0 . 2) The design value of capacity, NtPJ, of .the sub-pipe in tension at joints

shall be calculated by the following formula:

wheree, - angle between the axis of sub-pipe in tension and axis of main

I I pipe.

I - 95 - 1

d, Notes: 1. The limits o j applicability of this Clause m e : 0.2 < 8 < 1 . 0 , - < 50 (where t, - wall t,

thickness of the sub- pipe) and fl > 30°.

W l m d / t > 50, d/t = 10 is taken.

2. The X joint d K joint in this sectiun ~ e j m to tikt all Ute azes of the p i p members of the joint

shall lie in same plune.

11. Light steel structures of round bars and small d e s

11. 0. 1 The provisions in this chapter apply only to the light steel structures

of round bars and angles of small size (smaller than L45x4 or L56x36x4)

for buildings with span not greater than 18m and with light - or medium-

duty travelling cranes of capacity not more than 5 tons. Note :when small steel angles are used individually as secondory members in s t e e ~ h r ~ e s , the design m y not

be governed by provisionS in this chapter.

11. 0. 2 The provisions in this chapter do not apply to the light steel structures

that need special requirements for complex service conditions, such as struc-

tures subject to direct dynamic loads, and those under high temperature, high

humidity and strongly corrosive environments, etc.

11. 0. 3 The design value of strength for light steel structures shall be taken as

those specified in Clauses 3. 2. 1, 3. 2. 2 and Clause 11. 0. 6 respectively

multiplied by the following reduction factors :

'1. tension member with twin round bars in arches and its connections 0. 85

2. main compression web member at end panel of the latticed plane purlins

and the inclined latticed rafters of three - hinged arches 0.85

3. other members and connections 0: 95

. 11. 0. 4 The centroidal axes of truss members shall be concurrent at joints as possible, otherwise the effects of eccentricity shall be considered.

11. 0. 5 For the built-up inclined latticed rafter with triangular section of

the three - hinged arch roof truss, the ratio of depth of the section to length

of the inclined rafter shall not be smaller than 1/18, the width -to- depth

ratio of the section shall not be smaller than 2/5.

11. 0. 6 When a single round bar used as compression member is connected to I !

one side of a gusset plate, the member shall be checked for stability according

to Formula (5. 2. 2- I ) , and the welded connections may be calculated ac-

cording to Formula ( 1 1. 0. 8 - 1) , but the design value of weld strength

shall be multiplied by 0. 85.

When a single round bar used & tension member is connected to one side of a i i

gusset plate, both the strength of the member and its connections may be cal- 1 culated as those of the axially loaded tension member, but the design value of I I

I I

strength shall be reduced by 15 percent. I

1 11. 0. 7 The slenderness ratio of the main compression members in truss

(such as chord member, end diagonal and end vertical member) should not

be greater tha 150, the slenderness ratio of other compression members

should not exceed 200.

The slenderness ratio of tension members should not exceed 400, but that of I I the tightened rod is not limited.

1 Round bars should not be used for the compression chord member and com- 1 pression end diagonal of trusses. I I

I 11. 0. 8 For welds between round bar and flat plate (steel plate or plate part

I

of the steel shape, Fig. 11. 0.8-1 ), or between round bars

1 (Fig. 11. 0. 8 - 2) , the shear strength shall be calculated by the following

I formula :

I where N - axial force acting at the connection ;

I , - effective length of the weld;

he - effective thickness of the weld : he = 0. 7hf for connections be-

tween round bar and plate ;

he = 0. l(dl + 2d2) - a (11.0.8 - 2) for connections between round bars;

dl - diameter of the larger bar;

d2 - diameter of the smaller bar;

a -distance from the surface of the weld to the common tangent line

of two bars (see Fig. 11. 0.8-2).

Fig. 11. 0. 8 - 1 Welds between round bar and plate

Fig. 11. 0. 8 - 2 Welds between round bars

I

11. 0. 9 For welds between round bars and between round bar and flat plate I

(steel plate or plate part of steel shapes), the effective thickness shall not be I I

less than 0. 2 of the diameter of the round bar (when two bars with different I

I I

diameters are welded, the average diameter is taken) or 3mm, nor shall it I

exceed 1. 2 times the plate thickness; the effective length of the welds shall

not be less than 20 mm.

, ~. . -. . - - . . . . . , !

,,: . 1 1. ... 0. , _ _ _ 10 The _ . . . . . thickness --- of steeLplatk should$ott be l w h g 4mm. The diam- -----. . -. . . - .- ^ .-----;- . . - . - . - --.- :.--. . . . 2.- ----

. - - - . . - --.. . _ . .. ._ . .. . .

, .. . , . __ -..__ . -. ' - . .. -;

I . ? . .. eter of round bars should not be less than the following values: i . . . ~.

. . j For members of roof truss 1 2 mm 1 . For members of purlin and tie rod betwwen purlins

For bracing members . 8 m m l

16 mm I i

f . ' 1 2. Composite steel and concrete beams

1 2. 1 Genaral requirements

12. 1. 1 The provisions in this chapter apply only to the simply supported I

I

composite beam composed of concrete flanges and steel beam interconnected

by means of shear connectors when the composite beam is not subject to dy-

namic loads directly.

The concrete flanges (slab) of composite beam shall be designed according to I

provisions of relative code.

, 12. 1. 2 The effective width, be , of concrete flange (Fig. 12. 1. 2) shall be

calculated according to the following formula:

where bo - width of the top surface of the concrete haunch :

bo shall be calculated with a = 45' when the inclination of the

hauncha < 45' ; bo shall be taken as the width of the top flange

of steel beam when there is no concrete haunch;

bl , bt -effective width of the concrete flanges on the outside and in-

side of the steel beam respectively, each taking the lesser of

1/6 of the beam span, I , and 6 times the thickness of the

concrete flange. Besides, blshall not exceed the actual over-

! hanging width, sl , of the flange ; and b2 shall not exceed 1/

2 of the clear distance between two adjacent concrete

haunches.

When the composite beam is an interior one, bl is equal to b2 in Formula I

. (12.1.2). i

.. . .. ,

. , . . aunch

-

Slab . -

A. . . , - . ' Steel beam

Fig. 12. 1. 2 Effective width of concrete flanges

1 12. 1. 3 When the strength of the composite beam is calculated according to

provisions in this chapter, considering development of plasticity over the en-

tire composite section, the design value of strength of the steel component

shall be taken as that specified in Clauses 3. 2. 1 and Clause 3. 2. 2 multiplied

by a reduction factor, 0. 9. Calculation of deflection of composite beams shall be made in accordance with

I

the elastic theory. The concrete area of a composite cross section may be

transformed to steel by dividing the effective width of the concrete flange by

the elastic modular ratio of steel to concrete, aE , for the combination of

short -term load effects, and dividing it by 2aE for the combination of long

-term load effects.

The section of the concrete haunch may be ignored during the calculation of

both strength and deflection.

12.1. 4 When the steel beam is not propped during construction of the com-

posite beam, the weight of the materials and the construction loads applied

prior the hardening of the concrete shall be carried by the steel beam. The

strength, stability and deflection of the steel beam shall be calculated accord-

ing to the provisions in Chapter 3 and Chapter 4. '. . %.. .

. .

12. 2 Calculation of sections and shear connectors

# - 102 -

12. 2. 1 The flexural strength of composite beams shall be calculated accord-

ing to the following provisions:

1. When the plastic neutral axis is within the concrete flange

(Fig. 12. 1. 1 - I ) , that is, when Af < behclfm :.

M < bezfcmy (12.2.1-1)

Plastic neutral L-yLd axis I Ml----L Fig. 12. 2. 1 - 1 The composite section and the stress diagram

when the plastic neutral axis is within the

concrete flange.

where z -distance from the plastic neutral axis of the composite section to the I

top surface of the concrete flange, shall be calculated as follows:

Af x = - be fcm

M - bending moment due to the total loads;

A - cross-sectional area of the steel beam;

y - distance from the stress resultant of the steel beam section to that

of the compression zone of the concrete section;

f - design value of tensile, compressive and bending strength of steel

used in plastic design, see Clause 12. 1. 3 ; f,,- design value of compressive strength of concrete in bending. .

2. When the plastic neutral axial is within the steel beam section

(Fig. 12. 2. 1- 2), that is, when Af > behClfm ,

. - Plastic neutral axis LA -

Fig. 12. 2. 1-2 The composite section and the stress diagram

when the plastic neutral axias is within the

steel beam section

M < behelfmyl + A f y z (12.2.1 - 3) where A, - cross-sectional area of the compression zone of the steel beam,

shall be calculated as follows

A, = 0 . 5 [ A - b.h*l f, f

(12.2.1- 4)

yl - distance from the stress resultant of the tension zone of the steel

beam section to that of the concrete flange section;

yz - distance from the stress resultant of the tension zone of the steel

beam section to that of the compression zone of the steel beam

section.

12. 2. 2 The total shear force of the composite beam section is assumed to be

carried only by the web plate of steel beam and shall be calculated according

to Formula 9.2. 2.

12. 2. 3 The total number of connectors, n , of a simply supported composite I

beam provided in the region from point of maximum bending moment to the l

end of the beam may be calculated as follows:

where V - longitudinal shear force of the composite beam between concrete

flange and steel beam in the region from point of maximum

bending moment to the end of beam, and it shall be calculated

according to the following provisions : - 104 -

V = Af , when the plastic neutral axis is within the concrete

flange section ;

V = be hclfm , when the plastic neutral axis is within the steel beam

section.

X - design value of capacity in shear of a connector, shall be calcu-

lated in accordance with the provisions in Clause 12. 2. 4.

12. 2. 4 The design value of capacity in shear of a connector shall be calculat-

ed in accordance with the following formulas:

1. Headed stud connectors (Fig. 12.2. 4a)

Fig. 12. 2. 4 Shear connectors

where - cross-sectional area of the stem of the stud;

f - design value of tensile strength of the stud;

Ec - elastic modulus of concrete;

fcc - design value of axially compressive strength of concrete.

2. Channel connectors (Fig. 12. 2. 4b)

N: = 0 . 26(t f 0. 5tw)lc d G (12.2.4-2)

where t - average thickness of the flange of channel;

t, - thickness of the web of channel ;

1, - length of the channel.

3. Bent -up bar connectors (Fig. 12. 2. 4c) I

N: = Alfut (12.2.4-3)

where Al - cross-sectional area of the bent -up bar ; I f,, -design value of tensile strength of the steel bar. I

Note: Other types of connectors may be used on ~eliubik basis,

- 105 -

12. 3 Requirements for detailing

12. 3. 1 The depth of the section of steel beams shall not be less than 1/2. 5 of the total depth of the composite beam section. When the plastic neutral ax-

is is within the steel beam section, the width - to- thickness ratio of plate ele-

ments of steel beams shall meet the requirements of Clause 9. 1. 4.

12. 3.2 The depth of the concrete haunch of composite beams should not be

greater than 1. 5 times the thickness of the concrete flange. The width of the

top surface of the concrete haunch should not be less than 1. 5 times the depth

of the haunch.

12. 3. 3 The connectors calculated according to Formula (12. 2. 3) maybe

spaced uniformly along the beam axis between the points of maximum and

zero moments. When there are comparatively large concentrated loads acting

I between these two points, the total niunber of connectors required shall be di- I

I

vided in parts according to the ratio of their areas of the shear force diagram I

I and the connectors in each part are then arranged uniformly. I

I The spacing of connectors in the direction of beam span should not exceed I four times the sum of thickness of concrete flange and depth of concrete I

I haunch.

, L 12. 3. 4 The height (length) of the headed stud connector shall not be less I

than 4d ( d being the diameter of the stud). Studs shall be firmly welded to

1 the top flange of steel beams by means of special automatic stud welding ma-

chine and special processes. The spacing of studs should not be less than 6d in

the direction of beam span, and 4d perpendicular to the direction of beam

span.

12. 3. 5 The direction of the flange tip of channel connectors shall be consis-

tent with that of the horizontal shear stresses of concrete flange with respect

to steel beam. The welds between channel connectors and the top flange of

. - - ,

steel beam shall be calculated according to the relative provisions in Chapter

7.

12. 3. 6 Bent-up bars should be of Grade I steel (mild steel) with diame-

ters, d , not less than 12mm and be placed in pairs symmetrical about the beam axis. Each bent -up bar should be welded to the flange of steel beam

with two side fillet welds not less than 4d in length for each weld. The angle

of bend is, in general, 45' , and the direction of bend shall be consistent with

that of the horizontal stress in concrete flange with respect to steel beam. In the region where the shear stress may change sign, bent - up bars must be

placed in both directions. The total length of the bent-up bar from the point

of bend to its end should not be less than 25d including a horizontal segment

not less than 10d (for Grade I steel, a hook shall be added in addition at the

end).

12. 3. 7 The underside of the head of studs or the inner face ~f the top flange

of channel connectors shall extend over 30mm above the bottom reinforce-

ment of the concrete flange,

The thickness of concrete pro%ective covering above the top surface of connec-

tors shall not be less than 15mm. The distance from the surface of the stem

of studs or the end surface of channel connectors shall not be less than 20mm

to the edge of top flange of steel beam, nor less than 40mm to the edge of

concrete haunch, nor less than lOOmm to the edge of the concrete flange.

12. 3. 8 The top surface of the steel beam shall not be painted. Before placing

(or erection) the concrete flange, the rust, slag, ice piece, snow, earth and

other miscellaneous things shall be cleaned out.

Appendix 1 Overall stability factor of beams . .

Al. 1 Simply supported beam of uniform welded I-section

The overall stability factor of simply supported with uniform welded

I-section (Fig. Al. 1) shall be determined by the following formula :

where pb -factor of equivalent bending moment for overall stability of

beams, given in Table Al. 1 ; 4 = l,/i, -slenderness ratio about the weak axis y-y of the portion

of the beam between laterally supported points, 11 taken -:. as in Clause 4. 2. 1 , i, being the radius of gyration of the

gross section about the y-axis ;

A -gross sectional area of the beam;

h , tl -beam depth and thickness of the compresion flange, respective-

qb - factor of unsyrnrnetry of the section :

qb = 0 for doubly symmetric I- section (Fig. Al , l a )

qb = 0. 8 (2ab - 1) for singly symmetric I - section with en-

larged compression flange (Fig. A l . lb )

r)6 = 2ab - 1 for singly symmetric I-section with enlarged ten-

sion flange (Fig Al. l c )

where ab = 11/ (I1 +I2) , I1 , I2 being moment of inertia about the

', y-axis of compression and tension flanges respec-

tively.

p, shall be replaced by 9; of Table Al. 2 in case its value given by the

Formula (A1 ) is larger than 0. 6 0. Note: F m u l u ( A l . 1 ) k also valid for roUed vide flunge I-section a d riveted (or high- strength

bolted) simply supported beams of uniform section. For the lutters the thickness of the compressbn flunge tl

shall include that of the flunge angk. .

Pactor, fib ,simply supported beams of I- section Table A l . 1

Item

No.

1

.Votes ( f o r Table Al. 1)

1. < = lltl/blh -parame&, see Clause 4. 2. 1 for the values of bl d l 1 . 2. MI ,Mz are end moments of the beam, having same sign when musing curvatures of same sign and

vice versa, (MI I 2 IMz) .

3. Concentated loading in items 3,4 and 7 denotes one single load or a few w&ated 2mds n e a ~ the

mid- span, for 0 t h cbses of concentrat& loading Pb shaU be token from items 1 ,2,5 and 6.

4. In items 8 and 9 , Pb shall be token equal lo 1.20 when cwenCraled h& act on tlre IataaUy sccp

5

6

7

8

9

10

ported points.

5. Loading acting at the upper flonge denotes that acting on the flonge surface and pointing toward the

centroid of cross section in direction; loading acting at the lower flange denotes that acting on the flonge SUT-

face but pointing auay from the centroid in direction.

6. For I-section with enlarged compression flunge so as a, > 0. 8 , the value o f /lb shall be multiplied

by a coefficient as foUms:

0 .95 for ZtemNo.1 When5<l.o

0.90 for Item N o . 3 W h e n 5 < 0 . 5

0 .95 forItemN0.3WhenO.5<<<1.0

Lateral support

No intermediate

lateral

support

One lateral

support at

mid - span

Not less than two

intermediate

equally spaced

SUPporB

I

Applicability Loading

Uniform

load

acting at

Uniform load up*r flange I. I5

acting at

1=lltl/(blh)

1 4 2 . 0 1 0 2 . 0

0.69-l-0.131

1. 73-0. 20E

upperflage

lower flange

Concentrated

load

acting at

Subjected to end moments,

without any transverse

load between supports

0.73+0.181

2.23- 0.281

upper flange

lower flange

1. 75-1.05(M2/Ml)+O. 3(M2/M1I2

but not larger than 2. 3

Concentrated load

acting at any level

0.95

1 .33

1.75

1.20

1. 40

Any kind

of load

acting at

On1 y for

sections

1.09

I. 67

For all

sections of ,

Fig A l . 1

upper flange

lower flange

a&-b

in fig A l . 1

qb -factor of unsymmetry of cross-sections :

For monosymmetric I-section (Fig. Al . l a ) ??a = 0 For doubly symmetric I-section (see Fig. Al . l b , c) :

With enlarged compression flange q, = 0.8(20b - 1) With enlarged tension flange

- where ob = 11 - I1 and I2 being the moments of inertia about y-axis of .

I1 + I2

the compression flange and tension flange respective-

ly* When the value of cp,, calculated according to Formula (Al. 1) is larger

than 0. 6 0 , Q, shall be replaced by the corresponding m- in Table (Al. 2). Arote: Formula ( A l . 1 ) is applicable lo simply supp-ted wide - flange I beams and riveted (or high -

strength-bolted) beams of constant cross-section. The thickness of compression flange of the latter

beams includes'the thickness of flange angb.

Fig. Al . 1 Welded I-section

(a) doubly symmetric ; (b) with enlarged compression flange ;

(c) with enlarged tension flange

Overall stability Factor, 9; Table A l . 2

Note: 9. in this table is calculated from the following expression:

9 - = 1.1 - 0.4646/9 + 0. 1269/pla3/'

A l . 2 Simply supported beam of rolled I-section I

The overall stability factor, vb , of simply supported beams of rolled I-

section shall be taken from Table A l . 3. Values of qb larger than (). 6 shall be

replaced by the corresponding value of 9; in Table A l . 2.

A 1. 3 Simply supported beams of rolled channel -section

The overall stability factor qb of simply supported beams of rolled chan-

nel-section shall be calculated by the following expression without regard to

the pattern of loading and the position of load application point along the

beam depth.

i 570bt 235 v a = - * - (Al . 2) l lh f v

where h , b , t -depth, flange width and average flange thickness of the chan-

nel section respectively.

Value of tpb larger than 0. 6 obtained from Formula (Al . 2) shall be replaced

by the corresponding values of 9; in Table A l . 2.

Factor, cp, ,of simply supported beams of ordinary rolled I-section

Table A l . 3

Notes: 1. Bme as notes (3 ) , (5) of table A l . 1

2 . Values of in this table applies to steel p a & 3 and shull be rnultiplkd by 235/f,

fm other stel pa.

Al. 4 Cantilever beams of doubly symmetric I-section

The overall stability factor, g>a , for cantilever beams of doubly sym-

metric I - section may be calculated by Formula (Al. '1) but the factor Pb shall be taken from Table Al . 4 and Zl of 3, = Zl/iv shall be taken as the can-

tilever length. The calculated values of qb larger than 0. 6 shall be replaced by

the corresponding values of g>b in Table Al. 2. Factor, #Ib , for cantilever beams of doubly symmetric I-section

Table Al . 4 Item

No.

Note :This table is based on the condition that tlae supported e d is IT&!& ~esErained. M w e s shall be t u h I

to increase the hsional capacity at the support when using values o f this table for an ove~halanging beam

I

extending from adjacent span.

hdhg wun

Al. 5 Approximate calculation of overall stability factors

The overall stability factor g>b of uniformly bent beams may be calculated

by the following approximate formulas in case

1. I- section

.$=l~t/(bh)

0.60<5<1.24 1 1.24<.$<1. 96 I 1.96<5<3.10

1

2

3

h2 f Y Doubly symmetric : qb = 1. 07 - - - 44000 235

(Al. 3)

(Al. 4)

One

concentrated

load on the free

end acting at

2. T - section (moment acting in the plane of symmetric axis about

0.21+0.67.$

2.94-0.655

0.624-0.828

upper flange

Lower

flange

x - axis)

Uniform load acting

at the upper flange

1) When the flange is in compression under the moment:

0.72+0.265

2.64-0.408

1.254-0.315

T - section composed of twin angles

1.17+0.03.$

2.15-0.155

1.66+0.10.$

9, = 1 - 0.00173, Jf,/235 T - section composed of two plates

2) When the flange is in tension under the moment,

Values of qb given by Formulas ( A l . 3) through (Al: 7 ) need not be re-

placed by qbSof Table A l . 2 when.Jarger than 0. 60. Values of % given by

Formulas ( A l . 3) and (Al . 4) shall be taken as 1. 0 when larger than 1. 0.

Appendix 2 Calculation of local stability of girder web

I

A2. 1 Web plate strengthened with transverse stiffeners

The local stability of panels of web plates strengthened with transverse I

stiffeners (Fig. 4. 3. la) shall be checked by the following formula :

where o -compressive bending stress at the edge of effective web depth due

to the average bending moment in the calculated web panel.

T - average shear stress of the web due to the average shear force in

the calculated web panel, T = V/h& ).

oc - local compressive stress at the web's edge, calculated in

accordance with Clause 4. 1. 3 , but with 9 = 1. 0 for all cases.

o,, oc,, and T, (in N/mm2) shall be computed as follows:

1. when o, = 0 , for any value of a/ho , or when oc # 0 , for panels

of ratio a/ho < 0. 8 : loot, 2

U, = 715(-) (A2.2) ho

where C1 -parameter, given in Table A2. 1. 2. when o, # 0 for panels of ratio a/ho > 0. 8

1) If o,/o is equal to or larger than that given in the Table A2. 2 - 114 -

1 0 ot, 0, = C2(-l2

ho where C2 -parameter, given in Table A2. 1

uc,,shall be calculated by Formula (A2. 3)

2) If uc/u is less than that given in the Table A2. 2 , o., shall be

calculated by Formula (A2. 2) and ~c,,by Formula (A2. 3 ) ,

but by entering in Table A2. 1 with a/2 instead of a for C1 . Parameters C1 , C2 Table A2. 1

Limiting value of u,/u Table A2.2

where ZI and Z2 - - lengths of long and shorbedge of panel respectively. iVo& : FV7m the load carsing local compressive strew a, is acting at the lension fZunge of the beam, the stub&

tg of web panels shaU be checked twice using Formula (A2.1) by assuming successively ua = 0 and u = 0 .

A2. 2 Webs strengthened with transverse and longitudinal stiffeners

The local stability of webs strengthened with transverse and longitudinal

I stiffeners simultaneously (Fig. 4. 3. l b , c) shall be checked by the following

formulas :

1. Panels between the compression flange and the longitudianal stiffener

where u,l , and zml (in N/mrn2) shall be computed separately as follows:

1 ) when u, = 0 , for any value of <I = a/hl , or uc # 0 , for 41 < 1

Ted calculated according to Formula (A2. 5) 2 ) when u, # 0 , for C1. > 1 , the checking shall be carried out twice.

In the first calculation

I

u,,,~ , .tml calculated according to Formulas (A2.8) , (A2. 5 ) respectively

In formulas (A2.8) and (A2.9) , = 2 is taken when > 2 I

In the second calculation, uml is calculated according to Formula (A2. 7) ; i u,,,~ according to Formula (A2.8) , but taking = 0. 5a/hl ; .t,l accord- I

I

ing to Formula (A2. 5). 2. Panels between tension flange and longitudinal stiffener

I

where u2 = (1 - 2hl/h0)u; uc2 = 0. 3 0 ~ ue2 , u,,,~ , T~~ (in N/mm2) shall be computed separately as f ol-

lows : I I

.tm2 calculated according to Formula(A2. 5).

I

The parameter Cl in Formula (A2. 12) is taken from Table A2. 1 by us- 1 I ~

ing a/h2 in lieu of a/ho . Take a/h2 = 2 if a/h2 is larger than 2. I Notes: 1. The longitudinal steffner ~ h a U be located at a distance ho/5 - ho/4 from the compression edge of

Be effective web depth.

2. When the Zoad causing local compressive stress uo i s acting at tenston flange of the beam, the bcal

stability of the web panels between the tension flange and the longitudinal stiff- shall be checked twice using

F m u l a ( A 2 . 1 0 ) by assuming successively ua2 = 0 (web subjected to u2 and z ) and u2 = 0 (web subjected

to uO2 = a, and z 1).

I A2. 3 webs strengthened with transverse ,longitudinal and short steffeners

The local stability of webs strengthened with transverse stiffeners to-

gether with longitudinal and short stiffeners in compressive on zone - 116 -

(Fig 4. 3. Id) shall be checked as follows: 1. Panels between compression flange and the longitudinal stiffener : Formu-

C

la (A2. 6 ) is still valid, but use a1 Fig 4. 3. Id) in lieu of a . 2. panels between tension flange and the longitudinal stiffener : use Formula (A2. 10).

* n . ) o l o - ~ h - O D - m ~ h ~ o e n m r n ~ o c n

N N m - m T a 3 V - h

n h w w N U I N O W S

0 D Y ) v -

N m m ~ a m m w ~ W W U I V ~ o r n m ~ N N N - L n W O C I . . . . . . . . . . . . . . . .

o o o o o o d d d d d 0 0 0 0 0 0 0 0 0 0 O O O C

I D W D 1 ) W e a W m h - u o = n

C ) - U I Q u a h h n U I N w o C 1 w o - - I n - w

9 m m o C ) U I N O m h

m w w m m m m m ~ o o ~ h S h ' 9 " y 7 7 " : ~ N N N M -

L O I O N . . . . . . . . . Q) = . . . . - - - C I ,

0 0 0 0 0 0 0 0 0 0 0 0 . 0 0 0 0 0 0 0 0 0 0 0 0 0

I - W ( o = S S l C 2 h n . P - ( O N h W I . 7 0.N 0 - UI O W W - ~ P I I - ~ N 0 m m m O D m

w 0 1 b n W O Y I - I W 9 9 O C ) N

L O O - m h N N N " 4

W T O Z ? ? ? ? I D . . . . . . . . . . . . . . . a . . . . F I * "

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 - h - c - e - w a m u a - h N

W * W - , h h - 9 W n

m w - N W U I O W N W

a a V N O W I n n - Q l h

N - m h h

0 E I O C n l D O D h h U n U I T - ( n f ) N N N N - r ( w . . . . . . . . . . . . . . . a . . . . . . . . . 0 0 0 0 0 0 0 0 0 0 ~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 j ( 0 m O W ~ m O O U I O C n c ~ m t o - h r n W N ~ W N

- - t o w - W n w N m

P V w v U ) w W m - m h

m o m w W w T m N N N N - -

( D u a r n N " ? ? 7 " . " . S h ; ' P Y Y . . . . . . . . . . . . . - - - -

C 0 0 0 0 0 0 O O O C I O 0 0 0 0 0 0 0 0 0 0 0 0 0 0

P U I h N N C a m w w N m O

w w - ? m - N w m N

3 0 0 m V ) " " O ! m m " h l - W U I V I

h - h N r n ' y o ? ? w ' e - a m U I m m h O L O - 0 r n m m r m

a - 0 0 0 0 0 0 . . . . 0 0 0 0 0 Y Y Y ? ? - - - CI

d d d d d a * . .

0 0 0 0 0 0 0 0 0 VIP- ul O r - O m h N - N m - w l o - ' m o o ~~~~~9 m e w o m PIN NO^

t - - w W s . . l w w - m w

. n " a * O o m m m m w h h w m u 7 - - m w v c o

. . . . . a . . ? ? ? " ! Y N ? ? . . . . r( * - d d d d d d 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

I . S O b ) m - h h O ) U I - N - = - I - - O V O O m h v N - O w m N - 9 o o m a m w

m n h o - W N h C Q O h W N O W t ' : ' C ? Y ' : ' ? m y w L O v n

N . . . . . . E i Y ? l ? * - * - 0 0 0 0 0

. . a . ~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 - O n h N U a h i o m m n m u a

N l c - r a h ~ m - d 0 - W " w w o o w . 3 E S 3 2 Z m U I n ( Y

o m m m s w w h w w t n y w m ? ? " . . . . . . . Y Y Y Y 1 - ' d d d d d 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O O O U I

O N O ( O B ( D O m h O O W

w a ) U I w w h V N O W

o q m e m w m . . . Y ' U Y ? ? - 0 0 0 0 0 d d d d d 0 0 0 0 0 0 0 0 0 0 - 0 6 0 0 0 0 0 0 0 0 0

- ( * P l l m W h m - 0 0 0 0 0 0 * N r n W U I

0 9 0 0 0 W h W m O .c - - n - - - n n r t C I N

u

( D O - - ' O W 9 m - e o O O ~ O Y ) ~ W N - o d ~ w e a - o w - 9 - W 9 W N - h - O W = - 0 h W N O W W m W s ) a m m y q q 0 3 ' : h W U I m e N Y N N . ? - I * - - . . . . . .

1 o o o o o o 0 0 0 0 0 d d d d d 0 0 0 0 0 d d d d i h u a 0 0 " O m l a m n h h U I N b B w w 0 m U ) m U I n N m o w - n c o v m w w c o w m v o & - N O W w u a s n . . . . . . . . . . . . . . . . Q) o m a n m w m h h w u a 2 - ~ o . o . N N - ? ~ ? - - - n . . 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 e o o o o 0 . 3 0 0

O D ( O ~ W - ~ e - w - m a - b - ~ O F I W ~ ~ - E . . P W J o m w - c s m ~ 0 0 0 ~ ~ - U I Q ~ U , - ~ W N O W h m - ~ m m m m m m ? y y 0 1 n ~ s a n m N N . N N ? . . . . R - w d . . . . . . . . . . . . . . . . . O O O O O O 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

g Z E 0 k E E g Z g z g & z g 2 Z l t 6 5 . 8 E S Z (D 4 7 3 9 9 7 " y y 3 9 9 3 4 1 ~ y r r y ? - - - - . . . .

ul 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Q .- ' : C o I

~ - - U I N - S h m h - h T O N V ~ 0 m 1 - ~ V I * m W . 0 Q ) h l C I O ) O 1 0 ~ 1 0 0 0 m W d m N W U ) r n - m h W W m

(d 9 o m m m m m m w b w q w 9 7 ? ? N . ? N ~ ? R - W - . . . . . . . . . . . . a . . . .

0 0 0 0 0 0 O O O O O 0 0 0 0 0 0 0 0 0 0 0 0 0 0

O N . O h W h - w m - U I . - . I W Q l h N N W O V rd O B h U a O 3 O h N W B -

9 h F I W N m w m * m h w - n n o s m s 2 m . . - . ~ W ? W = . . . . q y y y ? y y y y ? - - * - . . . . u - - 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

~ I

0 m m m O I m i FI

0 I

I - 0 0 0 0 0 0

- " a O 9 1 P -

+ Q) - I n C Y m I n C Y m - m l m O I n I n N I I n - ' C o C .

0 V)

m h I n ~ w m I n h h m C Y w - h v - m h I n l + C Y ( O W W O

$2 m m m m m m h W I n w * ~ - c I - - - 0 m m

? ? ? ? ? . . . . . . . . . . - n m 1 . 1 d i d d d d 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 . - 3 3 d - 1 -

W W U Y h m a D h O h C Y m U I m O U J h W O W - m m N

C 3 h I n C Y O D O W O O W O N Q l h W 1 I N h h m -

a 2 m m m o D a D h W I n m W O O ? ? Y - r ( n - I - - I o m m . . . . . . . . . . - - 1 - 1 d d d d d d 0 0 0 0 0 0 0 0 0 9 o o a o o - 0 0 0 0 . . 3 9

L C ) ~ W O W W W C Y O D U I a n m h c u m - -

h m m n m h ( Y m - + - m h I n - C Y w m m n -

t m U 3 U f - r ' - - - - I n w o m m . . . . .

0 0 0 0 0 0 o d d o d 0 0 0 0 0 0 0 0 0 0 ? ? 3 4 0 0 0 0

W W C Y W N U ) - b l a h 0 W ~ O - 9 O J I - U I C Y -

m w w m o m m o w c v m W m m m h l O h w - O o u - m

h h W I n w m m ? N ' Y C V - - n r ( C Y - o m . . . . . . . . . . . . . - - - I 0

0 0 0 0 0 0 0 0 0 0 d d d d d 0 0 0 0 A.

W W - U ) h C Y a D - h h C Y O h l h O ."

m w w m w - O l r ( C Y 0 l n O Q D W 9 0

n - C Y T T m m w m o w

h h W l n W m m m u a c u

C Y - - n - I C Y - 0 0 )

m m m m m w . . . . . . * . a . ll??? 7 7 7 9 ):I d d d d d d 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

- w m m m - r w m m - o - c y 9 0 0 9

a m m h - m w

o m m w a m w m w m o m w w m c n c u m r

m m w - o w m C I w m w r'i - 7 - C Y - I o m m m m m m w . . . . . " 1 ? ? ? ? - CI I_E~ d d d d d d o o o o o o o o o o

. . ? ? 0 0 0 0 0 0 0 0 0 -

0 0 m - m - C Y W m C Y - ' l a D N l l m h - W 0 . - O m W m - W ' Q ) W E

O B W W - h w m 1 l n h m h W U J - O

0 1 0 ( P m - m ? ? C Y

C Y - o m . . . . . ? 4 ? 9 ? ' 0 . . . . . . - - 7 y y q 0 0 0 0 0 d d o o d 0 0 0 0 0 0 0 0 0 -

m o m w - m e n v m t - m m ( 0 h l h l w o c v ' c m l r ) - m m o Q l h O - ~ m - v m N w N

w U ) I n - C I I W O n O V ) m m u l m h l h l

m ?S??"O.hC: . . . . . . . . . . . . " f C J C : . . . . 2 ,--- 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 9 0 0 0 0 0 0 0 - I n m m C Y m C Y m h - L 7 m h l

w - m ~ ~ m I n m C Y I - C Y

h m m ' m m - 9 - W V I

I n - w m I n w o o - W L n t O l l l l I m m O N . ?

I n - m N w 0 i S C " ' O h . h . . . . . . . . . m w m h z - - - -

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 d d d d .

- -

-

I - 0 0 0 0 0 0 O O O O C . 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I '

O h l - l h h W O C Y C Y O m W O O W - U ) o ( D m m h h - I h 0 m w L C ) m

r r r w r r r s O B h - - s h - - m Z ~ E w n o m O " U r a ! ' D W m y ' 0 . 7 7 . - ' I ? ? ? e a r ( - - - - . * - I d 0 . . . . . . . w 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 d d d d d 0 0 0 0

w m o - a c y m m m m N PI

o m m o o w - - - O h - I n - h m - W W V ) m W t D W h e )

O m h m C V m C Y m ( 0 h m * - I - - I L I

C Y w o U s m 0 0 1 U I m U B W m h W I n - T ? ? ? ? . . . . . w - - . . . . . . . . . . . ? 9 - 0 o o F ) o 0 , 0 0 0 0 0 0 0 0 0 0 0 0 0 0 d d d o o

O - 9 n h N C n a D r n h O O

= O h m - r - r ( v m 1

m o m w w m w h l m w

N 0 m - m W E I O O O W

w s m s U I Q ) m O D O D h W W I n 1 1 9 m m m N . ? W C Y C Y 3 -

LC) - m e h - 2 . . . . . . . . . d d d d d d d d d d d d d d o o 0 0 0 0 0 0 0 0 0 I -- -~ -. - - - - - ~ . . . . . . . . . . . . . . . . . . . . . . . . d d d d ; ; I ' I d d d d d d d d d d b 0 0 0 0 0 o o o o I a a w t - - P o r n m c o v c o m I n

a? m m 0 m O P U I n O 9

h h N O - O W r n O h

w w m l - C Y T C Y O ( D h

m c D m m m v m m . . . . . . . . . . . . . . I

m m m m w h w ' ~ . y y - - m n ( n ( ~ ~ C Y C Y . + - - 4 - 4 -

d d d d d 0 0 0 0 0 0 d o o o d 0 0 0 0 0 0 0 0 0

- - l o r n - V ) m W U 1 9 ,-, b m o h m C U w o m

~ n w m m m - N O m h

O l h W W s o r n ? c u C Y n r q - -

m - m r u W ' 4 L O . Y ' . . . . - , - , - -

d o o o d d d c ' o d 0 0 0 0 0 d d d d I - - -

0

o o m ( 0 m m ~ m m m m w C V w n i - m

V ) m m w t . O O h - I n - h ( n O h

- m w o m L s a h l o m t -

n w h h 0 C n Q ) O D Q D h W V ) V ) V * C O O ? :

w - r n ~ . . . . . . C: . . . . C Y ? p 1 1 7 C I , - , , - , -

l d d d d c d d d d d O O O O O 0 0 0 0 0 0 0 0 0 ." O N W N m m 0 ~ ' e O r n h

m m m h m 0 9 h - W

~ m ~ m - 0 - h 9 . 0 m

W O O N I P l n m n m h

C U O a o m ~ w m m c v w

' ? ? ? ' = 2 " . Y P I ' o . Y " t S " ? 0 1 ? C Y ? ? ? ? ? . . . . . * - - w w - 0 D 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

O W O N O O ~ w r m b 7 W O ~ U I O D O) O Cn h W W N W

m w h m - m u, m N h o m w m o m W U J O N ~ h a - *

O ) m O b b w V ) V W O o a N y N C Y - - - - - - o m o m . . . . . . . . . . . . . . . . . . . 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

7 9 9 9 0 0 0 0

~ w m o m - w - w w o o w h - o - ~ a - ~ h w m N

m u , b 0 ~ 9 w ~ 3 w - 0 o w m . - , a a I - W ~ N - O D m - w

m m 5 m . b . q L O w w O O O N N N - - - - - C I o m m m . . . . . . . . . . . 1 - 1 d d o o o o o o o o o d d d d d o o o o o 7 9 9 9 0 0 0 0

w ~ m m m m m m m m o - W O D O ( Y - h m n r - w

w m m w h l O W O . - , a a

O ( D N m m h l O l l N "

m o z z O y ? N . - l - . - , . - , - m

o o m m O.rn.f 4 h . q - - w o n , - . - l o o

a * . . . . . . . 1"l 0 0 0 0 0 0 0 0 0 0 0 d o o d d d d d d d 0 0 0 0

w 0 0 w h h m w - n , ~ h N N W V L a o o O r t O oa &a

m w m - m L O h o w a a w O h w . - , m 0 - 0 ) - - o m -

? ? ? ? ' ? 2 z = $ : 2 , m o o 0 0 0 0 0 d d d d d d d d d -

O W O N O O V O ) U J O W V ) O - - W - h w N m w - W O N b W 9 - N

N m T E ?:""" ""3 n r u & w - - . - , . - , - - - = a m . . . . . . . . . .

0 0 0 0 0 d d d d d ? . 9 ? 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

c ~ c ~ w c ~ - - m w o m - m ~ r ( w o O O I - ~ O W I C J

- W L O N O O W I T O N O w L a m

g g z = g z = z % % g ? ? ? ? ? - . - , - - - - 0 m w . . . . . .-, .-, . . . . . .

o o o o o o d d d d d . . 3 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0

~ ~ w h m m m n , u , n , r o ~ W ~ W I V w e m w w 00 -

N ( D W N 0 O o ( D 9 O N m w w m

O W N w w m 0 - w - w w l n w w n , O N N . W ( Y .-, 0 m m . . . . . 9 0 . 0 . 5 h . " . . . . . . . . . . . . . . . - , . . - , . - , 00

. - l O O O O O O O O O O 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .." h m h m w N r n L a N O

V W O h L a r n W L a O N .-, .-I.-,.-,--

r ( 0 m m . . . . . . . . . ? ? ? ? ? .-, .-, 0 0

0 0 0 0 - r r O O O O 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

- C O O - h W m N m W L n w m

O W ~ N W I D w m - c m e O O W L a O N

L a w b o n 0 O N N N ? . - , . - , - - -

. - , O B m w . . . . . . . . . . . . . . . . . . 1 ~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

? ? ? ? 3 0 0 0 0 0

0 ~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 r t N ( n - ? l O 0 0 0 0 0 W h m m o

0 0 0 0 0 - N O T L O w h - m O .-, - . - , - - . - , m N O 9 W N N N N N

- 0 h C I ) H N ~ O W ~ O D * 0 ) h 0 9 m W w o m h

m m L a w 0 W m L O w c 0 N N W - l

b w e r n ~ Z S g Z - = Q m N m m - . - l o o . . . . . . . . . . . . .

0 0 0 0 0 d d d d d O O O O Q 0 0 0 0

U J W W C ) O W O m - 0 0 2 W L O U I U 2 1 N I m L O O - m

~ W N C I C V ~ ~ O O m N U J W O D W w O N N O u , h

m m m c o m h y y u . y ? * m m N O n m m - m . - , o m O D 2;;:; . . . a . .-, .-, 1 ~ 1 d d d d d o 0 0 0 0 0

0 0 0 0 0 . . 9 9 ..I 0 0 0 0 - ,-

W N - w m w c o b - h u , m O N L O m

O m N N W w m w m o

w w o w w C ~ ~ ~ W N W 00 . - La 0 N . . . . . . . . . m m m . w . O h W W L a W O - - - - - . - , . - , O O ' I ? ? Y ? d d o o o o d d d d d - 0 0 0 0 0 0 0 0 0 0 0 0 0 0

~ V ) L O ~ L O - W V ) W O O h O w L O w w b - C ; u , W O

m h 0 0 0 - h - - ~ W O W O W 0 0 W W L O O N 9 m w m

m m m , , y w w L a 9 w . - , . - , - - - - o m - . . . . ? ? ? ? ? . . . . - , - 0 0

o o o o o o d d d d d 0 0 0 0 0 d d d d d 0 0 0 0 - - a - m w - w 9 0 - o w m h m m w h O N - ~ O

I 1 0 0 ~ 0 - W W L O ~ N

m w i Z w m * w w - 0 m m w :y?"D.O.h . h 9 ' 4 S S ? ? ? ? ? .-,.-,.-,-.-, . . . . a

" " 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 d d d d m - O m h w - N - h N h . - , O O r n 0 - w - h

N h

m W w m W O D r ( W J U , l - W V ) - C W . - l m h m 9 N W b m Q

n m. me m. w. w. 2 h w LO w 9. O O ~ N . ? .-,.-,.-,-- - 0 o m ! . . . . . . . . . . ? ? ? ? - 0 0 0 0 0 0 0 0 0 0 0 d d o o o 0 0 0 0 0 0 0 0 0 - - .

1 ,

.-

Factor, g, , for 15MnV 8r: -15MnVq steel Factor, g, , for 15MnV 8r 15MnVq steel Class a sections Table A3. 7 Class b sections Table A 3 . 8

Factor, g, , for 15MnV & 15MnVq steel Class c sections Table A3. 9

Where al , caz , a3 , - coefficients, taken from table A3. 10, in accordance with the classification of cross section of Table 5. 1. 2.

i A

0

.-- . . - - ,-I _ I - I 6 1 6 1 7 1 8 1 , 9

10 20 30 40 60

60 70 80 90 100

110 120 130 I40 150

160 170 180

. 190 200

210 220 230 2.10 250

-- -. - -

0 ~ 1 ~ ~ ~ ~ ~ 4

1 , he value of the Factor, g, , are Coefficients al , a2 , a3 I

calculated From the following expres- Table A3. 1 0 , sions :

g, = 1 - a1A2 i I 1

a . >

forA= -Js< 0.215 ; !

7.c i

1 i I

g, = -[(a2 + + A2> - f 2A2 i

! I ,/(a2 + a3A + Az)' - 4a2]

for A > 0.215

1.000 0.996 0.986 0.929 0.848 0.765 0.679

0.595 0.616 0.449 0.395 0.346

0.304 0.267 0.236 0.209 0.187

Oil67 0.151 0.136 0.124 0.213

0.103 0.0949 0.0874 0.0808 0.0749

0.991 0.968 0.889 0.807 0.722 0.637

0.555 0.479 0.421 0.370 0.324

0.285 0.251 0.222 0.198 0.177

0.159 0.143 0.130 0.118 0.108

0.0990 0,0910

0.08470.0840 0.0778

0.989 0.945 0.864 0.781 0.697 0.612

0.531 0.460 0.405 0.355 0.312

0.274 0.242 0.214 0.191 0.171

0.154 0.139 0.126 0.115 0.105

0,.0965 0.0888 0.0821

0.995 0.937 0.856 0.773 0.688

I I

0.604

0.524. 0.455 0.400 0.351 0.308

0.271 0.239 0.212 0.189 '

-0.169

.0.152' 0.138

1 1 I 0.125 ' 0.114 1 0.104

0.0957 :

! t

0.0881 I i 0.0814

0.993 0.962 0.880 0.798 0.714 0.629

0.547 0.472 0.416 0.365 0.320

0.281 -0.248 0.220 0.195 0.175

0.157 0.142 0.129 0.117.0.116 0.107

0.0981 0.0903 0.0834 0.0772

-

1.000

0,0760 0.'0755 1 ~ I - I j

- -- -- -.

0.999 0.954 0.872 0.790 0.705 0.620

0.539 0.466 0.411 0.360 0.316

0.278 0.245 0.217 0.193. 0.173

0.155 0.140- 0.127

0.106

0.0973 0.0896 0.0827 0.0766

0.999 0.983 0.921 0.840 0.766 0.671

0.587 0.509 0.443 0.390 0.342

0.300 0.264 0.233 0.207 0.185

0.166 0.149 0.135 0.123 0.112

0.102 0.0941 0.0867 0.0802

. -

0.998 0.Y7G 0.905 0.823 0.739 0.654

0.571 0.494 0.432 0.380 0.333

0.292 0.257 0.228 0.202 0.181

0.162 0.146 0.132 0.120 0.110

0.101 0.0925

0.08600.0851 0.0790

- - -

0.980 0.913 0.831 0.748 0.662

0.579 0.501 0.438 0.385 0.337

0.296 0.261 0.230 0.205 0.183

0.164 0.148 0.134 0.121 0.111

0.102 0.0933

0.0796

-

0.973 0.897 0.815 0.731 0.615

0.563 0.487 0.427 0.375 0.328

0.288 0.254 0.225 0.200 0.179

0.160 0.145 0.131 0.119 0.109

0.099% 0.09lt

0.0784

Appendix 4. Effective length factor for columns

Column effective length factor , p, for frames without sidesway

- - - -. . -. -- - Table A4. 1

1 1 1 1 3 4 I b Y J n l e i

hrotesl 1. Values of factor, j i , me calculaled from the equation

ulhere Iil , Iis-ratw of the sum of girder l i n m sliffnesses lo that o f column linear stiffness at the top

und bottom of the cnlculated column ~espctively.

2. The linear stiffness o f a girder is taken as zero when the gi~der is hinge-connected to the

column.

3. FOP columns of the bottom story : tab ICz= 0 for columns hinged to the foundation, and Kz

= 00 for columns rigidly fixed to the foundation.

Column effective length factor , p, for frames with sidesway I i - -. . Table A4. 2-1

Notes: 1 . Values o f faclor , p , are calculated from the Eq. n n

[ 3 6 1 < , ~ , - ( ~ ) ~ ] s i n + 6 ( ~ 1 + 1 < 2 ) - cos -=O P P P P

2 . Same as Table A 4 . 1

3. same as Table A4. 1

Effective length factor, p, for the lower portion of

double-stepped columns with free top '

- . -. Table A4. 5 0.05 0.10

, Scheme 0.2 0.3 0.1 0.5 1 0.6 I 0.7 0.8 0.9 11 .011 .111 .2 0 .210 .3 )0 .410 .5 0 . 6 ( 0 . 7 1 0 . 8 1 0 . 9 1 1 . 0 1 1.1 1 1 . 2

0.2 2.02 2.63 2.04 2.05 2.05 2.06 2.07 2.08 2.09 2.10 2.10 2.03 2.03 2.04 2.05 2.06 2.07 2.08 2.08 2.09 2.10 2.11 2.082.112.152.192.222.252.29 2.32 2.352.392.422.092.122.162.192.232.262.292.332.36 2.39 2.42 2.202.292.37 2.45 2.522.60 2.67 2.73 2.80 2.87 2.93 2.21 2.30 2.38 2.46 2.53 2.60 2.67 2.74 2.81 2.87 2.93 2.422.572.712.832.953.063.17 3.27 3 .373 .473 .502 .442 .582 .712 .842 .963 .073 .173 .283 .37 3.47 5.68 2.75 2.95 3.133.30 3.45 3.60 3.74 3.87 4.00 4.13 1.25 2.76 2.96 3.14 3.30 3a.16 3.60 3.74 3.98 4.01 4.13 4.26 3.133.383.603.804.004.184.35 4.51 1.67 4.82 1.97 3.153.393.613.81 4.00 4.184.353.624.68 4.83 4.98 - - - - - - - - - - - - - - - -

0.2 2.04 2.062.052.06 2.07 2.08 2.09 2.09 2.10 2.11 2.12 2.07 2.07 2.0:: 2.08 2.09 2.10 2.11 2.12 2.12 2.13 2.14 0.4 2.10 2.14 2.17 2.20 2.24 2.27 2.31 2.34 2.37 2.40 2.43 2.14 2.17 2.20 2.23 2.26 2.302.33 2.36 2.39 2.42. 2.46

0.4 0.6 2.242.322.402.412.542.622.68 2.75 2 .822 .882 .912 .282 .362 .432 .502 .572 .642 .71 2.772.84 2.90 2.98 0.8 2.472.602.732.852.973.083.19 3.29 3.383.483.57 2 .532 .652 .7 i2 .88 3.003.103.21 3.31 3.40 3.60 3.59 1.0 2.792.983.153.32 3.473.623.75 3.89 1.02 1.14 4.262.853.023.19 3.31 1 .493 .613 .773 .91 4.03 4.16 4.28 1.2 3.18 3.41 3.62 3.82 4.01 4.19 4.36 4.52 1.68 1.83 4.98 3.24 3-46 3.65 3.85 4.03 4.21 1 -38 4.54 4.70 4.86 4.99

0.2

I - - I : : :

XI ,N2 : axial

force of upper,

middle and lower 1.0

portions I

2.44~?:1~~2.~;~?.4~~.1.1~~2.?!~]2.~.1~2.77~2.73~.71~~.6~\?.~7~2.66\ 2.62 ? E " ? . >2.68 3 .213 .03? .03 2 .88 2 .852.8.12.842.84 2.85

Table A4. 5 ,

AToh: Tralucsof f a c h , p , ~ e c a ~ ~ a t e ~ f ~ ~ t h e e q u a t & ~ $ ~ * L . ~ - ~ - ~ ~ * + ~ . K , - L ~ ~ - . ~ B { P P f I + ? 2 ~ , - t g ~ - t n - - l = 6 P P

--

0 .4

2 -39 2 .73

2 .50

2 .82

3 .39 3 .73 4 .13 ----- 2.48 3 .61

5 . 0 0 4 . 5 7 4 . 3 6 4 . 2 6 4 . 2 1 4 .59

6 . 3 4 5 . 0 0 4 . 8 8 4 . 8 7 4 . 9 1

0 .3

2 .31 2.60

2 .54

2 96

3.44 3 .73 4.07

3 67 3:79

4.43

4.76

5 .574 .991 .68

0.7.

1 . 23 2 .46

2.07

3 .25

3 .63 3.86 4 .13

4'06 4:15

4.89

5 .15

0 .2

0 .4

0 .6

0 .8

1 . 0

1.2

1 . 4

0 .2 0 .4 0 .6 0 .8 1 .0 1 .2

0 . 2 0 .4 0 . 6 0 .8 1 . 0 1 .2

0 .2 0 .4 0 . 6 0 .8 1 . 2 . 1 . 4

0 . 2 0 .4 0 .6 0 .8

- 1 . 0 1 . 2

0 . 2 0 . 1 0 .6 0 .8 1 .0 1 .2

0 . 2 0 .4 0 .6 6 . 8 1 .0 1 .2

0 .2 0 .4 0 .6 0 .8 1 .0 1 .2

0 . 5 l 0 . 6

2.47 2 -86

2 .50

2.74

3.41 3 .80 4.24

3.37 3 .54

4 .194.05

1 .53

5 . 5 3 4 . 9 1 4 . 6 2 4 . 4 2 1 . 2 9 4 . 1 9 4 . 1 2

0 .20

2 .97

2.51

2 .69

3 .45 3 -86 4 .36

3.30 3 .60

3 .98

4 .53

4 . 4 9 4 . 3 6 4 . 2 7

0 . 7 1 0 . 8

2 .042 .042 .052 .0~2 .072 .082 .082 .092 .102 .112 .12 ~ . 1 0 2 . 1 3 2 . 1 7 2 . 2 0 2 . 2 4 2 . 2 7 2 . 3 0 2 . 3 4 2 . 3 ' I h . 4 0 2 . 4 3

2 .542 .61 3 .08

2 . 7 9 2 . 9 8 3 . 1 5 3 . 3 2 3 . 4 7 3 . 6 1 3 . 7 5 3 . 8 9 4 . 0 2 4 . 1 4 4 . 2 8 3 . 1 8 3 . 4 1 3 . 6 2 3 . 8 2 4 . 0 1 4 . 1 9 4 . 3 6 4 . 5 2 4 . 6 8 4 . 8 3 4 . 9 8

2 . 1 5 2 . 1 3 2 . 1 3 2 . 1 4 2 . 1 4 2 . 1 5 2 . 1 5 2 . 1 6 2 . 1 7 2 . 1 7 2 . 1 8 2 .242 .242 .262 .292 .322 .352 .382 .412 .4C2 .472 .50 2 . 4 0 2 . 4 4 2 . 5 0 2 . 5 6 2 . 6 3 2 . 6 9 2 . 7 6 2 . 8 2 2 . 8 8 2 . 9 4 3 . 0 0 2 . 6 6 2 . 7 4 2 . 8 4 2 . 9 5 3 . 0 5 3 . 1 5 3 . 2 5 3 . 3 5 3 . 4 4 3 . 5 3 3 . 6 2 2 . 9 8 3 . 1 2 3 . 2 5 3 . 4 0 3 . 5 4 3 . 6 8 3 . 8 1 3 . 9 4 4 . 0 7 4 . 1 9 4 . 3 0 --_-----_- 3.353.533.713.YO4.085.254.414.574.731.875.02

2 . 6 7 2 . 4 2 2 . 3 7 2 . 3 4 2 . 3 3 2 . 3 2 2 . 3 2 2 . 3 2 2 . 3 2 2 . 3 2 2 . 3 3 2 .52

2 . 8 3 2 . 7 4 2 . 7 3 2 . 7 6 2 . 8 0 2 . 8 5 2 . 9 0 3 . 9 6 3 . 0 1 3 . 0 6 3 . 1 2 3 . 0 6 3 . 0 1 3 . 0 5 3 . 1 2 3 . 2 0 3 . 2 9 3 . 3 f i 3 . 4 6 3 . 5 5 3 . 6 3 3 . 7 2 3 . 3 4 3 . 3 6 3 . 4 4 3 . 5 6 3 . 6 8 3 . 8 0 3 . 9 2 4 . 0 4 4 . 1 5 4 . 2 7 . 1 . 3 8 3.673.743.884.031. IB4.3E1.504.684.804.945.08

2.66 3 .333 :052 .932 .872 .842 .832 .832 .8~2 .842 .852 .87 3 . 4 5 3 . 2 1 3 . 1 2 3 . 1 0 3 . 1 0 3 . 1 2 3 . 1 4 3 . 1 8 3 . 2 2 3 . 2 6 3 . 3 0

3.51 3.98 4.50

1 0 0 3 . 6 0 3 . 3 9 3 . 2 6 3 . 1 8 3 . 1 3 3 . 0 8 3 . 0 5 3 . 0 3 3 . 0 1 3 . 0 0 3 .26 3 .48

4 . 2 9 3 . 9 7 3 . 8 4 3 . 8 0 3 . 7 9 3 . 8 1 3 . 8 5 3 . 9 0 3 . 9 5 4 . 0 1 4 . 0 7 4 . 4 8 4 . 2 1 4 . 1 3 4 . 1 3 4 . 1 7 4 . 2 3 4 . 3 1 4 . 3 9 4 . 4 8 4 . 5 7 4 . 6 6 4.704.4?4.474.624.604.714.821.945.075.195.31

4 .764 .264 .003 .C35 .723 .653 .503 .543 .513 .483 .46 4 . 8 1 4 . 3 2 1 . 0 7 3 . 9 1 3 . 8 2 3 . 7 5 3 . 7 0 3 . 6 7 3 . 6 6 3 . 6 3 3 . 6 2

3 .91

4.55

___ - - - - - - -

5 . 6 4 5 . 0 7 4 . 9 8 4 . 6 0 1 . 4 9 4 . 4 2 4 . 3 8 4 . 3 5 5 . 3 3 4 . 3 2 1 . 9 2 6 . 7 4 5 . 1 9 4 . 9 2 1 . 7 7 4 . 6 9 4 . 6 4 4 . 6 2 4 . 6 2 4 . 6 3 4 . 6 ! j 4 . 6 7 5 . 8 6 5 . 3 6 5 . l 2 5 . O O 4 , 9 5 4 . 9 4 4 . O 6 4 . 9 9 5 . O 3 5 . 0 9 5 . 1 5 6 . 0 2 5 . 5 5 5 . 3 6 6 . 2 0 5 . ? e 5 . 3 1 5 . 3 7 5 . 4 4 5 . 5 ? 5 . 6 1 5 . 7 1

0 . 9

2 .75 3.29

2 .56

--PA------

2 .62

3.64 4-18 4.78 ------ 3.21

3.85

4 .66

4 .16

2.68 3.18

----------

2.54

2.64

3.57 4.08 4.64

3,?3 3 .49

3.91 4 . 2 0 4 . 2 1

4 .60

4 .2 f

0 . 30 . 1 .2 0 . 2 I 0 . 3 ~ ) _ ( . r ~ \ - O ~ 1 1 .0

2.82 3.38

2.58

2.61

1.71 4.29 4.91

3.21 3 .503 .51

3.S9

4 .73 4 . 9 8 5 . 0 7 5 . 1 7 5 . 2 1 5 . 3 8 j . 4 9

1.1

2.88 3 .483 .67

2.61

2.61

3 .75 4 .39 5 .05

3 .20 3.54

3 .90 4 . 2 3 4 . 2 6 4 . 3 0 4 . 3 4

4 .80

4 . 0 6 4 . 0 2 3 . 9 8 3 . 9 5 1 . 1 3 4 . 1 0 4 . 0 9

t _ _ - 3.47 3 . 6 0 3 .77 3 .95 4.12 4 .28 4 .45 ---- 4 .60 4 .75 4 .90 6 .04

- 2 .10 2 .35 2 .76 3 - 8 0 3 .90 4 .53

2 .21 2.46 2 .87 3.39 3 .98

2 .09 2 .28 2 . 6 3 3 .09 3 .63 4 .20

2 .20 2 .10 2.75 3 .20 3.72

2.05 2.12

2.64 2 .25 2 . 1 9 3 .82 3 .20

2 .26 2 .36 2.54 2 .79 3 .11

2.12 2 .41 2 .89 3 -49 4.16 4 .84

2 .22 2 .51 2 .99 3.57 4 .22

2 .11 2 .38 2 .83 3 -39 4 .02 4 .68

2 .21 2 .49 2 .93 3.48 4 .10

2 .09 2 .nl 2 . 69 3 .20 3 .76 4.87

2 .20 2-13 2 . ~ 1 3 .30 3.85

2 .07 2.21 2 .48 2 .87 3 .33 3 .83

2 .19 2 .35 2 . 6 3 a .01 3.46

2 - 1 3 2 .44 2 - 9 5 s'58 4.27 . 4 -19

2.23 2.54 3.04 3.66 4.33

2 .05 2 .15 2 .33 2 .62 3 .00 1 . 4 1

2 .21 2 .33 2 .51 2 .83 3 .20

2 .08 2.25 2 .56 2.98 3 .48 4 .02 ------ 2.19 2 .38 2 .69 3 .10 3 .59

2 .06 2 .18 2 .41 2 .75 3 .17 3.64

2.20 2 .33 2.58 2.91 3 .32

2 .69 3 .07 3 .56 4 .12 4 .72

2.85 3 .06 3.38 P.82 4 .33 1 .90

3.38 3 .51 3 .80 4 .17 4 .62 5 .15

3 .95 4 .07 4 .29 1 .59 1 .99 5 .46 - '1.54 1.64 4 .82 5 .08 5 .41 5.83

2 .47 2.66 2.98 3.41 3 .80 4 .43 --------- 2.93 3 .09 3 .35 3 .72 4 .16 4.fi6 --- 3.48 3 .61 3 .83 1 .13 1 .51 4.96 --------- 4.10 4 .19 1 .37 4.61 4 .94 5 .31

1 .72 1 . 8 0 4 .95 5 .15 5 .43 5 .76

2 .45 2 .72 3.16 3 .72 4.34

4 . 8 7 - 5 . 0 1

2.83 3.06 3.44 3.94 4 .52 5.16

3 .32 3 .50 3.81 4.25 4.77 5.37

3 .86 4.01 4.26 4.62 5 .09 6 .63 - 4.43 4 .56 4.76 5.06 5 .47 5.95'

2 . 4 5 . 2 . 4 5 2 .70 3 .11 3 .64 4 .23

2 .84 3 . 0 6 3.41 3 .68 4 -13 6 .03 --- 3.35 3 -51 3.E0 4 .20 4 .70 5.26

3.90 4 .03 4 .27 4 .60 5 .03 5.54 - 4.48 4 .59 4 .78 5 .06 5.44 5.89

2.413 2 .67 3 .02 3 .48 4.111 4 .58

2 .89 3 .07 3.36 3 .76 1 .21 4-78

1 .13 3 .57 3 .80 1 .11 4.56 5 .05

4 .01 1 .12 4 .32 4 .59 4 .95 5 .38

1.82 .1.71 4 .87 5 .10 5.41 5 . 7 9

2.52 2 .67 2 .93 3 .27 3 .69 4 .15

3 .06 3 .18 3.39 3 .67 4.03 4 .14

3 .69 3.78 3.95 1 .18 4 .48 4.83

4 .35 4 .13 4 .56 4-75 5 .00 5.31

5 .03 5 .10 5.21 5 - 5 7 5 .58 5.84

2.63

2 .60

3.86 4 .50 5.18

3 .20 3.57

3.91

4 .88

2.46 2 .74 3 . 2 1 . 3 .80 4 .45 6 .14

2 .82 3-06 3 .47 4.01 4.62 6 .29

3 .30 3 -49 3 .83 4 .29 4 .85 5 .48 -

, 3 . 83 3 .08 4.26 4.65 5 .15 6 .73 --- 4.3E 4 .51 4 .74 5 .07 5 .51 6 .03

2.68 2 .79 2 .98 3 .24 3.5;; 3 . 92

3 .88 3.47 3 . f i l 3.E2 4.07 1 .38

4.15 4.21 4 .33 4 .49 4 .70 4.05

1 .93 4 .98 5 .03 5.21 5 .35 5.S0

5 ,72 5 .77 5 -85 5 .96 6 .10 6 .28

2 .49 2 .66 2 .95 3 .33 3 .79 4 .29

2 .98 3 .12 3 .36 2 .68 4.n8 4 .51

3 .57 3 .68 3.87 4.14 4 .18 4.28

1 .20 1 .29 1 .41 4.66 1 .95 5 .30

4 .85 4 .83 5.05 5 .24 5 .18 5.78

? .93 3 .02 3 .17 4 .37 3 .63 3 .94

3 . i q 3 - 0 5 3 .96 1 .12 1-32 4.57 -- 1 - 6 8 4 .73 4 .82 1 .94 3-10 5 . 3 0 - 5 - 5 0 5 . 6 2 c . 7 0 5 . '0 5.93 6 .10

6 - 4 9 6 .53 6 - 5 9 6 - 6 8 6 - 7 9 6 - 9 8

2 .57 2 .71 2 .93 3 .23 3.fi0 4-02

3 .18 3 .28 3 .16 3. ;0 4.01 4.38

3 .86 3 .04 4.08 4 .28 4 .53 4 .84

1 . 5 7 4 .64 4 .75 4.91 5 .12 5 .38

5 .30 5 .35 5 .45 5 .59 5 .76 5 .99

Effective length factor, p, for the lower portion of I

double - stepped columns with translation - free and rotation - fixed top

Table A4. 6 *

Scheme

6

Appendix 5 Classification of members and connections for fatigue calculation

Classification of members and connections Table A5. 1 - Item

No. Sketch Description

Base metal at locations without connec-

tion

1. Rolled I shapes

2. Steel plates

1) Both edges as-rolled or planed

2) Both edges auto- or semiauto-

flame-cut (the cutting quality shall

conform to the first class standard

given In "Code for construction and

acceptance of steel structures'!

Base metal adjacent to transverse butt

weld :

1. welds machined, ground flush and

examined by non-destructive

inspection (conforming to the first

class standard given in "Code

for construction and acceptance

of Steel structuresN

2. Welds inspected, conforming

to the f i s t class standard.

Base metal adjacent to transverse butt

weld connecting parts of different thick-

ness (or widths) , with weld machined

and ground to a smooth transition not

steeper than 1 in 4 , and examined by

non - destructive inspection to conform

to the first class standard.

Base metal adjacent to longitudinal butt

weld, with weld examined by non -de-

structive inspec- tion as well as appear-

ance and size inspection to conform to

the second class standard.

Base metal adjacent to flange-web con-

nection welds, with welds examined by

non - destructive inspection to conform

to second class standard

1. Single- plate flange

(a) Automatic welding

(b) Manual welding

2. Double-plate flange

Base metal adjacent to the end of the

transverse stiffeners

1. The weld-run does not stop at the

end of the stiffener (return

welding adoped) . I 1 ( 2. The weld-run stops at the end of the ( I

stiffener. &is& metal at locations where a trape-

zoidal gusset plate is welded to beam

flange, beam web and truss members

with butt welds, after welding, the tran-

sition is machined flush and ground to a

smooth curve, where no defeets due to

start -stop of weld -run shall exist. 5

Base metal at location where a rectangu-

8 - lar gusset plate is welded to beam flange

-4 o rweb , l>150mm. 7

I

9

1 0

11

12

Base metal of beam flange at the end of

cover plate (with transverse fillet weld

across the plate end).

Base metal at the transition region to the

transverse fillet weld.

Base metal at the end of welded connec-

tion with two side fillet welds.

\

Base metal at the end of welded connec-

tion with 2 sidihnd 1 transverse fillet

welds.

Base metal of gusset plate connected with

r+l 1 1 - , - - -

1 1 - t - + z Z t - m

I1 -&++ .

- E+j- ,

7

6

8

7

7

. 5

I

13

14

I

verse fillet welds, (the effective width

of gusset plate is calculated according to

the stress dispersal (angle equal to 30 1.

--

- '

Base metal at location of K - shape butt

ewlds, misalignment of two plate axes

being < O.l5t, with welds examined by

non - destructive inspec - tion and the

weld toe angle a<45 . I I

Aioles : 1. All the butt uelds must be fully penetrated.

15

.16

17

18

19

2. Fillet welds shall comply with the requirements in Clmrse 8. 2. 7.

3. In Item No. 16, the shem stress range A z = z-z,,. , where z,,+, is io be taken as positive when it

. -!*;-- - 1 . i

Fillet

weld

---

I1 rC

I

. c I ' s .- U

- I '

I 1 - I - . 2 , - 11

-k=s=*L- I1

is in the same direction as z, and negative when it is in t k oppo& direction of z,.

Base metal of cruciform at location of

the fillet welds joints, rnisalingnment of

two plate axes beiig < 0.15t.

Checked by the shear stress range deter-

mined with the effective area of fillet'

welds.

Base metal at location of riveted connec-

I

Base metal at locations of tie bolts and

void holes

Base metal at location of high strength

bolted connections

7

8

3

3

2

Appendix 6 Effective area of bolts

Effective area of bolts Table A6. 1

Xote :The cnlues of the effective a ~ w A, in tlre Table aTe calculated by the follouing formula:

- 135 -

I

~ Bolt diameter

d

(mm)

16

18

20

2 2

24

2 7

30

3 3

36

3 9

42

4 5

48

52

5 6

6 0

64

6 8

72

7 6

8 0

8 5

9 0

95

100

Pitch

P

(nun)

2

2. 5

2. 5

2. 5

3

3

3. 5

3. 5

4

4

4. 5

4. 5

5

5

5. 5

5. 5

6

6

6

6

6

6

6

6

6 -

Effective diameter

of bolt

d(mm)

14.1236

15.6545

17.6545

. 19.6545

21.1854

24.1854

26.7163

29.7163

32.2472

35.2472

37.7781

40.7781

43.3090

47.3090

50.8399

54.8399

58.3708

62.3708

66.3708

70.3708

74.3708

79.3708

84.3708

89.3708

94.3708

Effective area

of bolt .

k (mm2)

156.7

192.5

244.8

303.4

352.5

459.4

560.6

693.6

816.7

975.8

1121

1306

1473

1758

2030

2362

2676

3055

3460

3889

4344

4948

5591

6273

6995

Appendix 7 Conversion factors between legal and non-legal units of weights and measures

conversion table of non-legal units and legal units

Table A7. 1

Note: 1 N/mmZ = IMP.

Legal units

1 N

9.80665 N

1 N * m

9.80665 N m

1 N/mmz

0.0980665 N/mmz

1 J/cm2

9.80665 f/cm2

Names of quantities

Force

Moment

strength and stress

Energy (or work)

per unit area

Non - legal units

0.101972 kgf

1 kg f

0.101972 kgf m

1 kgf m

10.1972 kgf/cm2

1 kgf/cm2

0.101972 kgf*m/cm2

1 kgf m/cm2

Appendix 8 Explanation of words in this code

1. In order to treat -different situations according to their individual condi- I

k. tions during the implementation of this code, words denoting the different de-

grees of strictness of demands are explained as follows: 4 (1)Words denotirig a very strict or mandatory requirement:

"mustn is used for affirmation;

"must not" is used for negation;

(2) Words denoting a strict requirement under normal conditions :

"shall" is used for affirmation ;

"shall not" is used for negation ;

(3) Words denoting a permission of slight choice or an indication of the most

suitable choice when conditions allow:

Nshouldfl or "may" are used for affirmation ;

"should notn is used for negation.

2. Itbe in accordance with" or be in compliance with" are used to indicate

that it is necessary to implement items in this code according to other relative

Additional explanation List of chief editor unit, participating units and chief drafting 'people of this Code .

Chief editor unit:

Beijing Central Engineering and Research Incorporation of Iron & Steel

Industry

zhe jiang University

Chongqing Institute of Architecture and Engineering

' Institute of Metallurgy & Construction Engineering

Tsinghua University

Harbin Architectural & Civil Engineering Institute

Tianjin University

Central Research Institute of Building and Construction of MMI

Chongqing Iron & Steel Designing Institute

Tongji University

Taiyuan University of Technology

Baotou Engineering and Research Corporation of Iron and Steel Industry

_Institute of Project Planning & Research, Pvlinistry of Machine

BuildiW3 Industry

South China University of Technology

Dalian University of Technology

Zhengzhou Institute of Technology

Southeast University

Nanjing Architectural and Civil Engineering Institute

China Building Technology Development Center

Northeast Electric Power Design Institute

~ i n i i t r ~ of Electric Power

Chief drafting people:

Zhang Zhiquan

Wu Rendai

Li Dezi

Lin Xingshan

Li Yun

Shen Zuyan

Zhao Wenwei

Liang Zhihong

Chen Jizu

Xia Zhibin

Wang Guozhou

Wu Huibin

Liu Xiliang

Xia Zherigzhong

Feng Xiujuan

Yu Guoyin

Zhao SeaYuan

Zhu Pinru

Wei Mingzhong

Li Jihua

Chen Jianhe

Chen Minghui

Ren Xinhua

Chen Ji

Ma Qingru

Chai Chong

Sun Guoliang

Chen Shaofan

Li Ruihua

Huang Yourning

Pan Youchang

Guo Zaitian

Zhu Qi

Liang Qizhi r i

Yan Zhengting