structural connections

7/27/2019 Structural Connections

1/205

Bolts and Bolted Connection

1


2/205

To ics

9 General Information

9 Design Resistance of individual fastener

-

Rivet Connections

Preloaded Bolts

9 Desi n for block tearin

Worked Example

P n connect ons9 In ection bolts

2


3/205

General Information

Types of Bolts & Rivets Rivets

Bolts

Anchor Bolts

3


4/205

4


5/205

General Information

Types of Bolts on- re oa e o s

Class 4.6, 4.8, 5.6, 5.8, 6.8, & Class 8.8, 10.9

Class 8.8, Class 10.9

The yield strength fyb and the ultimate strength fub for bolts

are iven in Table 3.1 in EN 1993-1-8:

Bolt class 4.6 4.8 5.6 5.8 6.8 8.8 10.9

fyb(N/mm2)

240 320 300 400 480 640 900

fub(N/mm2)

400 400 500 500 600 800 1000

5


6/205

General Information

Tensile Stress Area

rea

Tensile Area As determined

at thread re iond(mm)

As (mm2)

12 84.3

16 157

20 245

24 353

30 561

Shank

Area Adetermined at shank

6


7/205

Positionin of Holes

Detailing requirement Holes dimensions

Minimum end distance Normal

Minimum edge distance

Maximum end and ed e+2 mm for M 16 up M 24

distance+3 mm for M 27 and bigger

Minimum bolts spacing

Maximum bolts spacing

Close fitting flushed bolts

clearance d < 0,3 mm

7


8/205

Positionin of Holes

e4

e3

ym o s or en e ge s ances an spac ng o as eners

8


9/205

Positionin of Holes

Minimum and maximum spacing and end and edge distancesor o s an r ve s are g ven n a e . n - - .

Table 3.3: Minimum and maximum spacing and end and edge distances

Distances andspacings

Minimum Maximum

End distance e1 1.2d0 4t+ 40mm

End distance e2 1.2d0 4t+ 40mmDistance e3In slotted holes

1.5d0

4

In slotted holes1.5d

0

Spacing p1 2.2d0 min{14t: 200mm}

Spacing p2 2.4d0 min{14t: 200mm}

9


10/205

Positionin of Holes

Failure modes in bolted composite joints:-

(b) shear-out failure;

(c) bearing failure

e1

p1

Ade uate End Inade uate EndDistance Distance

10


11/205

Positionin of holes

In compression between the fasteners, the local buckling

need not to be checked ifp1 / t < 9 and yf/235=

according to EN 1993-1-1 using 0,6p1 as buckling lengthand t is the thickness of the thinner outer connected part

For staggered rows of fasteners

Minimum line spacing ofp2 = 1.2d0

. 0

11


12/205

Desi n of Bolts

Single &

double shear

12


13/205

Desi n of Bolts - Shear Resistance

Shear Resistance in one Shear Plane1) When the shear plane passes through the

threads of bolt:

2

,

subv

Rdv

AfF

=

Where, v = 0.6 for Class 4.6, 5.6 & 8.8

= . . , . , .

10.9

f is the ultimate strength of bolt

As is the tensile stress area of boltrefer to NA to SS EN 199325.1=

13


14/205

Desi n of Bolts - Shear Resistance

Shear Resistance in one Shear Plane2) When the shear plane passes through the

shaft of bolt:

2

,

ubv

Rdv

AfF

=

Where, v = 0.6 for all Class

u

Ais the full area of bolt

= .2M

14


15/205

Desi n of Bolts - Bearin Resistance

Bearing Resistance

1

,

ub

Rdb

dtfkF

=

d0

25.12=

M

Where, dis the bolt diameter

2M

s e nom na c ness o e

connected plate

p1e1

u

b is the smallest of {d, fub/fu, 1.0}

For end bolts:0

1

3d

ed

= = 5.2,7.1-d,1.47.1-8.2min 02

0

2

1 dk

For inner bolts:4

-3

0

1

dd=

= 5.2,7.1-4.1min0

2

1d

pk

15


16/205

Resistance in Bearin

In oversized holes reduce bearing by 0.8

If load on a bolt is not parallel to the edge,

separately for the bolt load components

parallel and normal to the end

R 10 20

e30

Lp 1

1 IPE 200

14060

40

P 10 - 140 x 100

t t

e1 40

4

SdM 20 - 5.6

105,6 5010

10

16


17/205

Bearin Resistance of Bolt Grou

For holes 2 (end bolts)

p1 e1

p1=3d0 e1=1,2d0

4,03

2,1

3

01 ===d

d

d

e

F F

For holes 1 (inner bolts) Holes 1 Holes 2

If for individual fastener a l 1 if not 2 .

75,025,0125,03

25,03

0

0

0

1 ====dd

F Total bearing resistance based on direct summation

,,

525252 tdtdtd

Total bearing resistance based on smallest individual resistance222

,,,

MMM

Rdb

=+== ,

( ) ( )222

.

5,26,1

5,24,02

5,2

M

u

M

u

M

u

Rdb

ftdftdftdF

=+== 0,402

17


18/205

Desi n of Bolts - Tensile Resistance

Non-preloaded bolts in tension Simple method ignores prying action

Bolt resistance down-graded

More exact met o Full bolt resistance used

o a o orce

Ft = F + Q

Prying Action

18


19/205

Desi n of Bolts - Tensile Resistance

Tensile Resistance

2

,

sub

Rdt

AfkF = 25.1

2=

M

Where,fub is the strength of bolt

2M

As is the tensile stress area of the bolt

For countersunk bolts: k = 0.63

For regular bolts: k2 = 0.9

19


20/205

Punchin Shear Resistance

Punching Shear Resistance

,

6.0upm

Rdp

ftdB

= 25.1=

2M

t plate thickness

dm

the mean of the across points and

head or the nut, whichever is smaller

d wd ddd +

2d2

m=

20


21/205

Combined Shear and Tension

EdvF

RdvF

,

.0.14.1

,

,

,

,+

Rdt

Edt

Rdv

Edv

FF

0.5

01.4

EdtF,

. . Rt,

21


22/205

Reduction of Bolt Shear Resistance

When the thickness of steel packing tp exceeds d/3, thes ear res s ance s ou e re uce y p w c s g ven

by:

ptd

d

38

9

+= 0,1but

p

Packin lates

1,0

p

tp

,

t p00,3 d 1,5 d1,0 d

22


23/205

Effect of Lon Joints

If Lj > 15d, the design shear resistance Fv,Rd should bere uce y a re uc on ac or Lfw c s g ven as:

75,00.1but LtddLj

Lf200

151 =

1.0

Lf

0.75

0

0 15d 65d JL

23


24/205

Rivet Connection

Philosophy of design was used for bolts (class A)

Bolts spacing's recommendations came from rivets

able 3.3 for min and max spacing ofrivets & bolts

Clause 3.6 Design resistance ofrivets & bolts

24


25/205

Sli -Resistant Connections

The design slip resistance at ultimate of a preloaded class8.8 or 10.9 bolt should be tanked as:

nk

CPM

Rds ,3

, =

ere, s s e coe c en correspon ng o eren o es

(see Table 3.6)

Fp.CdCPF ,n n e num er o r c on p anes is the friction coefficient

p,C s.Rd

subCP AfF 7.0, =refer to NA to SS EN 199325.1

3=

M

25


26/205

Friction Coefficient

Tests -

preloading -Part 2 : Suitability Test for Preloading

Table for different classes of friction surfaces

With painted surface results in a loss of pre-load

Class of friction surfaces Slip factor A blasted, metal spraying

(EN 1090)0,5

,

C cleaned (EN 1090) 0,3

,

26


27/205

Values of k

Table 3.6 Values of ks

Description ks

,

Oversized holesor s or s o e o es w e ax s o e s o perpen cu ar o

the direction of load transfer

,

on s o e o es e ax s o e s o perpen cu ar o e

direction of load transfer0,7

direction of load transfer0,76

Long slotted holes

with the axis of the slot parallel to the direction of load transfer0,63

27

li i i bili


28/205

Sli Resistance at Serviceabilit

The design slip resistance at Serviceability of a preloadedclass 8.8 or 10.9 bolt should be tanked as:

snk

CPserM

serRds ,,3

,, =

re er o o.,3 =serM

or o s o pass e c ec , as o sa s y serEdvserRds ,,,,

28

C bi d Sh d T i


29/205

Combined Shear and Tension

If connection subjected combined tensile force Ft,Ed or Ft,Ed,serand shear force, the design slip-resistance per bolt should be

taken as follows:

For ultimate resistance

3

,CP,

,

8.0F

M

Edts

Rds

nkF

= 25.13 =M

For serviceability resistance:

serM

serEdtCPs

serRdsF,3

,,,

,,

.

= 1.1,3

=serM

29

D i f Bl k T i


30/205

Desi n for Block Tearin

Block tearing consists of failure in shear at the row of boltsa ong e s ear ace o e o e group accompan e y ens e

rupture along the line of bolt holes on the tension face of the

bolt rou .

Block tearing subject concentric load Block tearing subject eccentric load

30

Bl k T i R i t


31/205

Block Tearin Resistance

For symmetric bolt group subject to concentric loading

,1,

31nvyntu

Rdeff

AfAfV +=

Ant net area subjected to tension

Anv net area subjected to shear

For bolt group subject to eccentric loading:

02

,2,5.0

M

nvy

M

ntu

RdeffV

+=

25.12=

M

0.10=

M

31

A l t d th h L


32/205

An les connected throu h one Le

Where member are connected unsymmetrically

or the member itself is unsymmetrical (angles, channels,

account

For angles connected by a single row of bolts in one leg

he member may be treated as concentrically loaded

The design ultimate resistance based on a modified netsection

32

A l t d th h L


33/205


For an unequal angle connected by its smaller leg, Anet istaken as the net section area of an equivalent equal angle

e1

d0e2

1 bolt

202, /)5.0(0.2 MuRdu tfdeN =

33



34/205


e1 p1 e1 p1 p1

NA f

u.Rd2 net u

M2

=

2 boltsN

A fu.Rd

net u

M2

=

3

3 or more bolts

22 MunetRd,u /fAN = 23 MunetRd,u /fAN =

ere:

2 = 0,4 if p1 2,5 d0= 0 7 if 5 0 d

3 = 0,5 if p1 2,5 d03 = 0,7 if p1 5,0 d0

net = ne area o ang e

34

Worked Exam le 1 - An le connected


35/205

Worked Exam le 1 - An le connected

through one Leg

Design a single angle to carry an axial permanent action of

70kN and an imposed load of 35kN.

ry an 80 60 7 angle of S275 steel connected through thelong leg by a single low of two 20mm bolts in 22mm holes at

,

35

Worked Exam le 1


36/205

Worked Exam le 1

kN147355.17035.1loadDesign =+=

Design strength:

t=7mm = 275 N/mm2 = 430 N/mm2

( ) 293175.765.56 mmA =+=Net area

( ) 27777225.765.56 mmAnet

=+=

The s acin :

mmp 801= 64.3

22

80

0

1 ==d

p

s ng a e . , or n erme a e va ues o p c p va ues o

may be determined by linear interpolation

( ) 54.05.25

..5.264.34.0 =

+=

36

Worked Exam le 1


37/205

Worked Exam le 1

The ultimate resistance of the net cross section

kNfA

NM

unet

Rdu16410

1.1

43077754.0 3

2

,=

==

e y e ng res stance o t e sect on

Afy 275931 3

M

Rdpl0.1

0

,

kNkNNN 147164 >==

Design resistance in block tearing considering rows as staggered:

,,

130

45

37

Worked Exam le 1


38/205

Worked Exam le 1

2

nt==

2679733130 mm==

Afnvy

1

MM

Rdeff

6792752384305.0

.02

,2,

+=

kNkN 1473.1548.1075.46

31.1

>=+=

+=

The angle is satisfactory.

38

Worked Exam le 2 Fin Plate


39/205


3 x M20, 8.8

3510

meteril S235

P10 - 230 x 110HEA 200S235

IPE 300

70

S235

70

45

5

Sd

60

39



40/205


8045

70

70

70

70

230

50

50

45

In beam web

M0

nv

b1y,M2

b1u,

Rd,11 fV

3

,nt +=

100,1

1,711222220235

3

1

1025,1

1,711503605,033

+

=

40

kN1kN 991599.39 =+=



41/205


70

45

70

70 70

45

50

50

1In beam web

M0

b1y,

uM,

,

u,6Rd,

3

+=

0,1

,235

31,1

, +

=

41

. =+=

Pin Connections


42/205

Pin Connections

Pin connections in which no rotation is required may bees gne as s ng e o e connec ons, prov e a e

length of the pin is less than 3 times the diameter of the pin.

42

Desi n of Pin


43/205

Desi n of Pin

Given thickness t & d

20000dFdF

MEdMEd

3232 ftft yy

Given geometryc, a & do

FMEd 0

fy

,,0

43

Anal sis of Pin - Shear


44/205

Anal sis of Pin Shear

Resistance of one shear area of pin ins ear

0,6Af b

0.5FEd0.5FEd

EdV,

M2

RdV,

=

W ere, up s t e u t mate tens e strengt

of the pin

-pin

Fv,Ed = 0.5FEd

a ac c

FEd25.12 =

M

44

Anal sis of Pin - Bendin


45/205

s s o e d

Ultimate Resistance of the pin in bending 0.5FEd0.5FEd

bEdM

ypel

RdM

fWM =

0

5.1

Serviceability Bending ResistancedW8.0

serEd

serM

serRd ,

,6

,=

, yp

Wel is the elastic modulus of the pin,

c c

3

Ed

32

Wel=

1993ENtoSSrefer to0.16

=ser

0.10=

M

( )acbMEd 248

Ed ++=45

Anal sis of Pin Bendin & Shear


46/205

Fv,EdFv,Ed

b

resistance of the pin:

d0.1

2

,

2

+

EdvEd FM

,v

c c

F

acbEd 248Ed

++=46

Anal sis of Pin - Bearin


47/205

Ultimate Bearing Resistance of the pin and the plate

Edb

y

RdbF

tdfF

,,

5.1=

Serviceability Bearing Resistancetd.60

serEdb

serM

serRdb ,,

,6

,,=

ere, s e c ness o e connec e par ;

dis the diameter of the pin;

y

connected part;1993ENtoSSrefer to0.1

6=

ser

0.10=

M

47

Anal sis of Pin - Serviceabilit


48/205

If the pin is intended to replaceable, the contact bearing stresss ou sa s y

Rdhf

,Edh,

ddFEserEd 0,

)(591,0

=

t,

serM

y

Rdh

ff

,6

,

5.2

=

d the diameter of the pin;

d0 the diameter of the pin hole;

t the thickness of the connected part;

fy is the lower of the yield strengths of the pin and the connected part;

Ed,ser ,

the characteristic load combination for serviceability limit states

48

In ection Bolts


49/205

Injection bolts may be used as an alternative to ordinarybolts and rivets for category A, B & C connections.

Bolts of class 8.8 or 10.9

he design ultimate shear load of any bolt in a Category A

Preloaded injection bolts should be used for Category B

49

In ection Bolts Bearin Stren th


50/205

The design bearing strength of an injection bolt

sinre,bsinre,bst ftdkkF =

coefficient depending of the thickness ratio

4M

,,

fb,resin bearing strength of the resin

tb, resin

effective bearing thickness of the resin

kt 1,0 for serviceability limit state

1,2 for ultimate limit state

s , , - , ,

for oversized holes; mthe difference between the normaland oversized hole dimensions

50

In ection Bolts


51/205

1

2

1

2

t

t

1 0

1,33

112

22t

21 tt1.0 2.0 /

(EC3) Figure 3.5:Factor as a function of the thickness ratio of the connected plates

(EC3)Table 3.5: Values ofand tb,resin

,res n

2.0 1.0 2t2 1.5d< < -

1.0 1.33 t1 1.5d

51


52/205

52

To ics


53/205

Basis of design Fillet weld

Detailing requirements

Design model Simplified method for design resistance

Design example

long welds Connection to unstiffened flange

Full resistance of connecting members

Full Strength Butt Welds

-

53

The Heat Source


54/205

For structural steelwork the het source isan electric arc.

Arc heat is expended during the melting of

meta e ectro es as t s n t e eat ng o

base parts. Approximate values of arc

-

welding:

Dissi ation into the environment: 20 Transition with molten drops: 26%

apor za on o e ec ro e me a :

Absorption by base metal: 30%

54

The Heat Affected Zone


55/205

Melting point of steel 1400 1500.

Arc temperatures typically 6000.

- .

High temperature affects the structure of base metal. Grain

size enlarges at boundaries of the weld joint - in the heat

.

Outside the HAZ grain size is the

.

55

The Heat Affected Zone


56/205

The metal in HAZ have relatively poor mechanical properties.

56

Carbon Steel: Weldabilit


57/205

Carbon: Low C steels considered very weldable

Medium C steels fairly weldable

High C steels poor weldability Other alloys

Low alloy steels similar to medium carbon steels

Hi h allo steels enerall ood weldabilit undercontrolled conditions

Steels can be assessed in terms of the Carbon Equivalent

Value (CEV):

VMCCNSMCCEV oruiin +++++++=

57

Carbon E uivalent in Steel


58/205

CEV = 0.3 0.4 have a lowhardenability and are easy to

weld.

Grade(MPa) CEV limit (%)

CEV = 0.4 0. are more

hardenable and greater care is 275 0.44355 0.49

hardening.

CEV > 0.5 are much more

420 0.52

460 0.55difficult to weld because of

their high hardenability.460a 0.50

550a 0.83

690a 0.83

a: quenched & tempered

58

Residual Stress


59/205

Unhomogenous heatingcauses local thermal

expansion of metals. This is

after cooling.

stress in the center of a weld.

Tensile stress in a weld iscompensated by compressive

stress in base metal.

59

Residual Stress


60/205

During welding, edges move relative toeach other, mostlyperpendicular to

the welding direction.

Residual stress results in shrinkage of

.

make the distortion smaller.

The residual stress decreases as

annealing temperature increases.

60

Welded Connections


61/205

Four most common types of welds are introduced in EN

- -

Fillet welds(a)butt

Butt welds

Plu welds

roove we s

61


62/205

Transverse Longitudinal

Butt Joint Lap Joint

e we e we

Tee Joint Corner JointEdge Joint

62

e ym o s


63/205

(BS EN22553: 1995)

Additional symbols:

Weld all round Field weld

63

Detailin Re uirements for Fillet Weld


64/205

1. Fillet welds terminating at theL > Tw

continuously around the corners

for a distance > twice the legL

length s.

2. The length of the longitudinalTw

fillet weld L should be not less

than the transverse spacing Tw.

2s

min

3. In lap oints the minimum overlap

Lp should 4 times min(t1,t2). Lpt1 s4. Single welds should not be used

except where the parts are

the joint.

64

Detailin Re uirements for Fillet Weld


65/205

5. Single fillet welds should not be

longitudinal axis.

.

effective lengths of weld sw shouldnot exceed 300mm or 16t for

compression elements and 24t for

tension elements. incorrect

sw

65

Effective Throat Thickness


66/205

The effective throat thickness, a, should be taken ase perpen cu ar s ance rom e roo o e we

to a straight line joining the fusion faces.

For enetration fillet weld the throat thicknessaccount should be taken of its additional throat

thickness.

66

Effective Throat Thickness


67/205

Fillet weld often used for connecting parts where the fusionaces e ween an .

A simplified relationship of the throat thickness (a) and the

le len th s is iven in followin :Angle

between

Throat

thickness

60 67 0.87

sa=0.5sa=0.87s

68 - 74 0.8

75 -80 0.75

s s

60 120 81 90 0.7

91 100 0.65

Equal legged fillet weld101 106 0.6

107 113 0.55

114 - 120 0.567

Fillet Welds


68/205

Each weld transfers aong u na s ear Lan

transverse forces or shear

V and V between the

plates. The average normal and

shear stresses w and won the weld throat may be

forces

( )22 -sin-cos

LTzTyw

TzTyw

VVVLa =

=

68

Fillet Welds


69/205

It is

customary to assume that the static strength of the weld id

e erm ne y e average roa s resses w an w a one.

From Von. Mises Yield Criterion, the plane stresses must be satisfied

In which is the ultimate tensile stren th of the weld.

uwww f+

22

3

Substituting the foregoing two equations intouwww

f+ 22 3and rearranging leads to

( ) ( ) ( )22222 cossin2-3 LafVVVVVuwTzTyLTzTy

+++

This is often simplified conservatively to

aV

3

uw

L

LTzTyRVVVV ++=

69

Sim le Desi n Method


70/205

The simple design method of EC3-1-8 is based on thoseequa ons

3

uwR

L 222

LTzTyRVVVV ++=

loads are limited byFF

Where,

ww ,,

L

VF R

Edw=

,

(4.3)

,, dvwRdwfaF =

ee gra e u a vw,d a

S235 360 208

(4.4)

3

,

Mww

u

dvwf

=

S355 470 241

w is a correlation factor

70

Correlation Factor


71/205

Standard and steel grade Correlationfactor

wEN 10025 EN 10210 EN 10219

S 235 W

S 235 H S 235 H 0,80

S 275

S 275 H

S 275 N/NL

S 275 M/ML

S 275 NH/NLHS 275 NH/NLH

S 275 MH/MLH

0,85

S 355 N/NL

S 355 M/ML

S 355 H

S 355 NH/NLH

S 355 H

S 355 NH/NLH

S 355 MH MLH

0,90

S 420 N/NL

S 420 MH/MLH 1,00

S 460 N/NL

S 460 M/ML

S 460 NH/NLH

S 460Q/QL/QL1

S 460 MH/MLH

,

71

Desi n Model of Fillet Welds

EC3-1-8 also provides a less conservative directional method


72/205

EC3-1-8 also provides a less conservative directional method,

w ,breaks up w into and

e s ress mo e n

EC3-1-8

normal stresses perpendicular to the throat normal stresses parallel to the axis of weld (omitted)

s ear stresses perpen cu ar to t e ax s o we shear stresses parallel to the axis of weld

72

Desi n Model

22


73/205

Based on the criterion , the design resistance ofuwww f+

22

3t e et we w e su c ent t e o ow ng are ot sat s e :

222 f.

2Mw

II

2

.and

M

u

Where, fu is the ultimate tensile strength of the weaker part joined;

w

1993ENtoSSrefer to52.1=

73

Two Fillet Welds under Parallel Shear


74/205

=

a

II2

From plane stress analysis is

throat thickness,

not le len th

32Mww

u

a

74

Fillet Weld under Normal Shear


75/205

0=II

2

R ==

Has to e sat s e

uf22

MWw

uf

=+ 222

2232MWw

uf MWw

2

75

Cantilever Bracket


76/205

Shear force SdSd FV = Transferred by web fillets

Bending moment

aSdII

=

Transferred by the shape of weld

eSdSd

=

Centre of gravityIwe and cross section modulus Wwe

For weld at lower flange cross section modulus Wwe,1 and

stress is:

1

11 2we

Sd

W

M

==

For upper weld on flange is:

2

22

2we

Sd

W

M==

76

Flan e Web Weld

Welds are loaded by longitudinal


77/205

Welds are loaded by longitudinal

VSd

ls ear orce:

SVV Sd=

Where, VSd is the shear force

to neutral axis

I is the moment of inertia

This longitudinal force is carried by two welds

effective thickness, a, shear stress:

uI

II

f

a

V

32 =Maximum stress is at the point of maximum shear force

77

Worked Exam le Tension Member


78/205

To avoid torsion due to the applied force acting at aneccentricity C = 30mm, b1 < b2

Simple methodTake moment about b2,

b1 Plate

( )( )

aCF

aaabCFw

+=

-

or2/

2

1

a=100

C

F=250kN

From force equilibrium

w 21 b2 100X100 angle

( )21

b--

or

aF

b

babFw

=

++=

w

78


Use 6mm fillet weld, for longitudinal weld.mmkNw /94.0=


79/205

mmb 8.291002

100-

94.0

30250 2

1=

=

136mm29.8-100-94.0

2502 ==b

,

We get, b1 = 35mm and b2 = 145mm.

Directional method

Use 6mm fillet weld

For longitudinal weld:

mmkNRdLw

/94.0,,

=

= tw ,,

79



80/205

Moment about b2( )2/

1aaabCF

wtwL +=

2

( ) mmb 6.181000.942

1.15-302501

=

=

Force equilibrium

( )wtwL

abbF ++= 21 -

-or b

aFb wt

=

wL

125mm8.61-94.0

1.15001-5022

=

=b

one eg eng an roun e o e neares mm,

We get, b1 = 25mm and b2 = 130mm

80

Lon Welds


81/205

In la oints the desi n resistance of fillet weld should be

reduced by multiplying it by a reduction factor Lw to allow the

e ects o non-un orm str ut on o stress a ong ts engt .

//// // //

Lw

81

Lon Welds


82/205

In lap joints longer than 150a, Lw should be taken as Lw,1given by:

2.0

Lj

Lj is the overall length of the lap in the direction of the force

.150

.1,

aLw

transfer.

1,Lw

1.2

0.6

Lj

0

a82

Lon Welds


83/205

For fillet welds lon er than 1.7metres connectin transversestiffeners, Lw should be taken as Lw,2 given by:

L

17

.2,Lw

=

6.0&0.1but2,2,

LwLw

Lw is the length of the weld (in meters).

2,Lw

1.1

0.6

0

(m)w0 8.51.783

Connections to Unstiffened Flan es

Effective width of an unstiffened T-joint


84/205

84


For unstiffened I- or H-section, effective width beffshould be


85/205

o a ne rom:

tkstb 72 ++=

, = fyfft

, pyp ft

y, fy,p is the yield strength of the plate

or a ro e I- or H-sect on

for a rolled I- or H-section

rs =

as 2=

85


For unstiffened column flanges,


86/205

( )0

,,72

ybfb

fcwcRdfct

ttkstF

++=

t fb

Where

= 1;bb

fcyc

tf

tfk min

twc is the web thickness of column

fc s e ange c ness o co umntfb is the thickness of beam flange

beffrc

yb s e y e s reng o eam

fyc is the yield strength of column

t fctwc

86

Weld Desi n for Full Resistance of

Connecting Members


87/205

t

w

= FSd/ (t h)

Mwuf /

,

t

FSd the acting design force

fu plate design strength

t t e t nness o connect ng p ateb width of connecting plate

ttf My )10,1/235()/( 0f

Mwu

,,25,1/360

,/

,

87

Weld Desi n for Full Resistance of

Connecting Members


88/205

Sd

Mwwfa

/85,0>t= VSd / (t h)

VSd the design shear force in weld

full capacity of a plate the thickness S235

ttttf

ta My 4,036,0)31,1/(23585,0)3/(

85,085,0 0 ==>

MwuMww

,

88

Full Stren th Butt Welds

Full penetration butt welds are formed when the parts are


89/205

connec e oge er w e c ness o e paren me a .

For thin parts, it is possible to achieve full penetration of the.

For thicker parts, edge preparation may have to be done toachieve the weldin .

The types of butt joints:

89

Desi n of Full Stren th Butt Welds

Wled reinforcement


90/205

Wled reinforcementparent metal if matchingelectrodes are used.

Throatthickness

Matching electrode specified Backing member

,strength, elongation at failureand Charpy impact value each

equ va en , e er an, osespecified for the parentmaterials.

90

Throat Thickness of Partial Penetration

Butt Welds


91/205

The specified penetration should 2t, t is the thickness ofthe thinner part jointed.

The throat thickness of partial penetration butt welds, a,

should be obtained by:

mmaanom

2-=

91

Throat Thickness of T-butt Joints

Full penetration T joints


92/205

Full penetration T joints

taanomnom

+2,1,

andtcnom mm3nomc

Partial penetration with an effective

w

mmnom,1 21 = aa

nomnom ,,

Partial penetration butt

mmnom,2

22

= aa

penetration butt weld

92

Stress Distribution in Butt Weld


93/205

along the weld length is

often assumed.

It is true for plasticredistribution of stresses.

In elastic stage, especially

fatigue design, the actual

stress is much higher thanthat of the parent metal.

93

Stress Distribution in Butt Weld


94/205

should be avoided occurring

at sharp re-entrant corners

in joints.

To reduce the stress

concentration, the gradual

to the other is recommended.

stress concentration94

Root O enin

Root opening is used for electrode accessibility to the base orroot of the joint


95/205

Root opening is used for electrode accessibility to the base orroot of the joint.

The smaller the angle of the bevel, the larger the root opening

mus e o ge goo us on a e roo .

If the root opening is too larger, more weld metal is required.

45 60 30

3mm6mm 9mm

Root opening

95

Weldin in Cold Formed Zones

Welding may be carried out within a

length 5t either side of a cold formed zone


96/205

length 5teither side of a cold formed zone,

if one of the following conditions is fulfilled:

o - orme zones are norma ze a er

cold-forming but before welding -

Maximum thickness (mm)

r / t Fully killed Aluminium-killedsteel

(Al 0,02 %)

25

10

any

any,

2,0 1,5

12

10

1,0 6

96


97/205

for Structural Analysis(this part for information only)

97

Introduction to Joint Desi n

Frame components

B Beam Joint


98/205

Beams

Beam-columns

Beam Joint

Joints

Beam-column

98

Introduction to Joint Desi n

The lecture covers all the structural joints which are usually met

in a building frame:


99/205

g

beam-to-column joints (A)

beam splices (B)

column splices (C)

column bases (D)

C

A

C

A A

D D

Different t es of oints in a structure

99

o n an onnec on


100/205

Left connection

ConnectionLeft joint Right connection

single-sided joint

configuration

double-sided joint

configuration

100

Joints Classification

Classification of joints according to rotational stiffness:

Simple (pinned) joints


101/205

Simple (pinned) joints

Semi-rigid joints

Rigid joints

101

Joints Classification Rotational Stiffness

A joint may be classified according to its rotational stiffness, by

comparing its initial rotational stiffness Sini

with the boundaries.


102/205

102

Joints Classification Column Bases

Column bases may be classified as rigid provided the

following conditions are satisfied:


103/205

g

in frames where the bracing system reduces the horizontal

displacement by at least 80 % and where the effects of

deformation may be neglected:

If

If

;5.00

( ;/1-27&93.350. 0,0 CCini LEIS


104/205

resistance Mj,Rd.

Full-strength joints: design

resistance that of theconnected members & No

Full-strength

j

plastic hinge.

Partial-strength joints: TheMj,Rd

bending resistance < that ofthe connected members.

Partial-strength

n p nne o n s, e es gn

resistance is quite limited

and it is therefore neglected. Pinned

Boundaries for strength

Joint strength104

Sources of Joints Deformabilit

The bending moment Mb in the beam may be reduced to two

statically equivalent forces (one in tension, one in


105/205

y q ( ,

compression) acting in the beam flanges.

b

single-sided joint

configuration

double-sided joint

configuration

105

Joints Modellin

In a single-sided joint configuration, two main contributions

o e e orma on o e o n are e ne :Th d f ti f th l b l i h


106/205

The deformation of the column web panel in shear;

The deformation of the connection in bendin .V

wpNc2Mc2

V

c2

Vb1Vb1

Mb1

b1Web panel in shear

V

b1

Vc1

Mb1

Mb1

Nc1

Connection in bending106

Joints Modellin

For simplify, a single-sided joint configuration may be

mo e e as a s ng e o n ;


107/205

and a double-sided joint configuration may be modelled as two

- .

107

Joints Modellin

When determining the design moment resistance and

ro a ona s ness or eac o e o n s, e n uence o eeb panel in shear sho ld be taken into acco nt b means of


108/205

web panel in shear should be taken into account by means of

the transformation arameters and where:

2-1 .2,1 =EdbjM

,1, Edbj

2-1.1, = Edbj

M

1 is the value of for the right-hand side joint;

,2, Edbj

2 is the value of for the left-hand side joint.

will be used to determine design resistance of basiccomponents of joints

108

Joints Modellin

A simplified method to determine the approximate for 1 and

2 s s own n a e . n - - :


109/205

109

Joints Modellin

For frame design, the following joint modelling types are

usually made available to designers:


110/205

-

rigid / partial-strength

As soon as the concept of semi-rigid joints is well accepted,

new available joint modelling types be identified:

- -

semi-rigid / partial-strength

110

Semi-Ri id Joints

Modellin of oints elastic desi n

M


111/205

Mj Mj Mj

rigid joint pinned joint semi-rigid joint

111

Semi-Ri id Joints

The influence is not limited to the moment distribution; the

e ec ons, e o er n erna orces, e co apse mo e, ecollapse load are also affected by the joint properties


112/205

collapse load are also affected by the joint properties.

p nne rame sem -con nuous rame

112

Joints Modellin & Frame Anal sis

Stiffness Resistance

Full-strength Partial-strength pinned


113/205

Rigid Continuous Semi-continuous *

Semi-rigid Semi-continuous Semi-continuous *

Pinned * * Simple

* Without meaning

Modelling Type of Frame Analysis

Elastic Ri id- lastic Elastic- lastic

Continuous Rigid Full-strength Rigid/full-strength

Semi- Semi-ri id Partial-stren th Ri id artial-stren thcontinuous Semi-rigid/full-strength

Semi-rigid/partial-strength

s mp e nne nne nne

113


114/205

ruc ura onnec ons

114

To ics

9 General

9 Component method


115/205

9 Basic com onents

9Resistance -

Equivalent T-stub in compression

Bending moment resistance

9 Rotation capacity

115

General

A joint may be represented by a rotational spring connecting

e cen re nes o e connec e mem ers. e proper es othe spring can be described by the relationship between the


116/205

p g y p

bendin moment M and the corres ondin rotation .,

116

Structural Pro erties

The design moment-rotation characteristic includes three

main structural properties:

Moment resistance (M )


117/205

Moment resistance (Mj,Rd)

e es gn momen res s ance j,Rd s equa o e

maximum moment of the design moment-rotationcharacteristic.

Rotational stiffness (Sj)

he definition of S applies up to the rotation atwhich Mj,Ed first reaches Mj,Rd, but not for largerrotations.

Rotation capacity (Cd)

Cd is equal to the maximum rotation of the design- .

117

Different A roaches

Experimentation

Curve fitting

Finite element analysis


118/205

Finite element analysis

S mp e ana yt ca mo e s Component Met o

M Experiment

Function hl bt M 531=

ta

118

Decomposition of joint

Column web in tension Component description


119/205

Components in tension

Components in compression Classification

Web panel in shear

Column web in compression

Modelling in analyses

Joint

119

Basic Com onents of a Joint

The structural properties of basic joint components re given

n a e . o - - . For example:

VEd


120/205

p

1. Column web panel in shear

2. Column web in transverse com ression

Fc,EdVEd

3. Column web in transverse tension

Ft,Ed

4. Column flange in bending

- F

t,Ed

.

6. Flange cleat in bending Ft,Ed

,

etc.

120

Basic Joint Components (Table 6.1)


121/205

121

E uivalent T-Stub in Tension

In bolted connections an equivalent T-stub in tension may

e use o mo e e es gn res s ance o e o ow ng as ccomponents:


122/205

end-plate in bending;

base plate in bending under tension.

n mF

Leff

BB

122



123/205

123


Failure modes

Mode 1: Complete yielding of

T,Rd


124/205

p y g

QQ

0.5 FT,Rd+Q 0.5 FT,Rd+Q

Mode 2: Bolt failure with

ieldin of the flan e

,

FT,Rd

0.5 FT,Rd+Q 0.5 FT,Rd+Q

Mode 3: Bolt failure.

Where, FT Rd is the design tensionresistance if a T-stub flange;

Q is the prying force.

0. T,Rd 0. T,Rd

124


F/2F/2 F/2 For Mode 1 without backing

Q Q

p a es, e es gn ens onresistance given as:


125/205

un mQ Q

or4

F,1,

RdT,1, m

Rdpl=

d wd wforces)prying(no

2F

,1,

RdT,1,m

Rdpl=

F/2 F/2F/4 F/4F/4 F/4Where,

Q/2 Q/2Q/2 Q/2

0

2

1,Rdpl,1,

/25,0MMyfeff

ftl =

n m

Q Q

C

C

125


For Mode 1 with backing plates. lheffbp 1,

ebpMMRdbRdl 1

24 +de

bp2


126/205

MMRdbpRdpl ,,1,

24 +p

ebp

2

mRdT,1,

forces)prying(noF,,

RdT,1,m

=

,

0

2

1,Rdpl,1,/25,0M

yfeffftl =

0,

2

1,Rdbp, /25,0M Mbpybpeff ftl =

tbp 126


Where, m, emin, tfand leffare s indicated as following:


127/205

-

127


For Mode 2:

nm

FnMRdtRdpl

+

+= ,,2,

RdT,2,

2F


128/205

nm +

For Mode 3:

Rdt,RdT,3,FF =

,02,2 /25,0 Myfeff,Rdpl, ftl =

mn 25.1nbute =

Ft,Rd is the design tension resistance of a bolt.

128

E uivalent T-Stub in Com ression

In steel- to-concrete joints, the flange of an equivalent T-stub

n compress on may e use o mo e : the steel base plate in bending under the bearing pressure on

the foundation


129/205

the foundation

the concrete and/or grout joint material in bearing.

The design compression resistance of a T-stub flange FC,Rdshould be determined as follows:

jdeffRdC, bF fleff=

ere, eff s e e ec ve w o e -s u ange

leff is the effective length of the T-stub flange,

jd

129

E uivalent T-Stub in Com ression

The area of equivalent T-stub in compression may be

e erm ne as o ows:


130/205

03

Mjdf

tc

= ere: s e c ness o e -s u ange;fy is the yield strength of the T-stub flange.

130

Desi n Resistance of Basic Com onents


For a single-sided joint, or

For a double-sided joint in which the beam depths are similar,


131/205

The design plastic shear resistance Vwp,Rd of an unstiffened

column web should be obtained using:

,

,

3

9.0vcwcy

Rdwp

AfV =

Where, Avc is the shear area of the column,

- - .

131



Where a column web is reinforced by adding a supplementary


132/205

web plate, the shear area Avc may be increased bybstwc.

ome re n orce me o s g ven as:

Examples of cross-section with longitudinal welds

132


2. Column web in transverse compression

Transverse


133/205

compression on

an unstiffened

column

133



The design resistance of an unstiffened column web subject

to transverse compression should be determined from:


134/205

1

,,

,,

0

,,

,,but

M

wcywcceffwc

Rdwcc

M

wcywcceffwc

Rdwcc

ftbkF

ftbkF

=

Where,

is a reduction factor see Table 6.3 in EN 1993-1-8

0.110==

MM

wcywcfk

,Edcom,7.0if0.1 =

beff,c,wc

is the effective width of column web in compression,

wcywcywc ,Edcom,,Edcom,.-.

see c ause . . . n - - .

134



is the reduction factor for plate buckling

72.0if0.1 = p


135/205

( ) 72.0if/2.0- 2 >= ppp

2

,,,932.0

wc

wcywcwcceffp

Et=

The column-sway buckling mode of an unstiffened columnweb in compression should be prevented by constructional

res ra n s.

Column-sway buckling mode135



Table 6.3: Reduction factor for interaction with shear


136/205

136


3. Column web in transverse tension

The design resistance of an unstiffened column web subjectto transverse tension should be determined from:


137/205

,wt,,

,,

wcywcceff

Rdwct

ftb

F

=

Where, see Table 6.3 in EN 1993-1-8;

or a o e connec on,eff,t,wc

= e e ec ve eng o

equivalent T-stub;

Ft,Ed

or a we e connec on,

( )statbfcbfbwcteff

+++= 522,,

sectionrolledforcrs =

c

137


4. Column flange in transverse bending Ft,Ed

For welded joints,

bfb

bceftb

=


138/205

0

,

M

Rdfc

=

ere, eff,b,fc s e e ec ve rea eff e ne n c ause .

For unstiffened column flange, bolted connection, thedesign resistance and failure mode should be taken as

-

each individual bolt-row required to resist tension;

-

138


4. Column flange in transverse bending

Definitions ofe, emin, rc, and m


139/205

139



Effective length (Leff)

Circular failure


140/205

Circular failure

Single bolt

Bolt group

Single bolt

o group

140



Circular Failure FF


141/205

F

FF

2 r r = m

r = n

Virtual work

r/2

/2

= x

/2

cpeff,

141



Effective lengths for an unstiffened column flange


142/205

142


5. End-plate in bending

n en -p a e n en ng s ou e rea e as an equ va enT-stub flange.


143/205

Modelling an extended end-plate separate T-stubs

For the end-plate extension,

x

x

mm

ee

=

=

143


1,42= 8 p2 5,5 4,75 4,45

Bolt in Corner

1,2Circular patternseffective length

1 0L


144/205

1,0mLopeff

,

=

0,8

em

m

+=

1

,

em

m

+=2

2

0 2

,

0,0

0,90,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 1144


5. End-plate in bending

- . - -


145/205

145

Design Resistance of Basic Components

6. Flange cleat in bending

o e ang e ange c ea n en ng s ou e rea e as anequivalent T-stub flange.


146/205

Effective length leffeff of an angle flange cleat

146


6. Flange cleat in bending

Influence of Gap

ra emin ra emin

m0 8

m0 5 t


147/205

0,8 ra 0,5 t a

g 0,4 t a g 0,4 t a>

g 0,4 ta g > 0,4 ta

a

Effective length eff = 0,5ba

147

Bendin Moment Resistance

The design moment resistance may be derived from the

es gn res s ances o s as c componen s o n erna orces.


148/205

zRdtRdj ,,

=F

Where, z is the lever arm;

z

,

M j,Rd

,

of tensional flange.c,Rd

148


For bolted connection one bolt row

= i iRdtiRdj zFM ,,


149/205

Ft.Rd

Ft.Rd

zz Fc.Rd Fc.Rd

149


Determination of the lever arm z for beam-to-column joints


150/205

z z

z = - fb

z z

150

Rotational Stiffness

Deformation of a component Rotation in Joint

Fi

i= i

i

j

=

i


151/205


Fi

i

i

i

j

j

j

EzEz

F

zFzFMS

111

222

==

==

Where, ki is the stiffness coefficient for Ziii

KKz

as c o n componen ;

zis the lever arm;

s e s ness ra o.

151


The stiffness ratio should be determined from:

j

inij

S

,=

if RdjEdj MM


152/205

if RdjEdj MM ,, 3

1, ==j

inij

S

if RdjEdjRdj MMM ,,,3

==Rdj

Edj

j

inij

MS

S

,

,,5.1

Type of connection

.

Bolted end-plate 2.7

Base plate connections 2.7 152

Rotational Stiffness The stiffness coefficients ki for basic component should be

determined from Table 6.11 in EN 1993-1-8:

Component Stiffness coefficient ki

Unstiffened Stiffened

Column web

l i h


153/205

panel in shearAvc38.0= =

Unstiffened Stiffened

VEd

z1 1

Column web in

compressionFc,Ed wcwcceff

tb,,

7.0

Other Stiffened weldedcd

2 2

o umn we ntension

connec ons connec ont,Ed

wcwctefftb

k,,

7.0= =

cd 3

153

Continue

Component Stiffness coefficient ki

Column flange

Ft,Ed

3

34

.k

fceff=


154/205

34

m

End-plate in

bending

Ft,Ed

39.0 tl

peff=35

m

Flange cleat in

bending Ft,Ed 39.0 tlaeff

36 m

154

E uivalent Stiffness

For end-plate joints with two or more bolt-rows on tension, a

s ng e equ va en s ness coe c en eq e erm ne rom:

iiieffzk ,

eq

eqz

=


155/205

eq

Where,Mj

zz z1 2 =

effk

1

1

iik

z 1= i

iieff

eq

hk

zkz

,

z4i

,

155

Rotation Ca acit

For plastic global analysis

For basic safety

M

uc e componen s

M


156/205

Plate in bending j.RdM

Column web in shearCd

Brittle components

bolts

welds

,

156

Rotation Ca acit

Deem to satisfy criteria

Welded joints

Unstiffened 015,0min, =Cd

Unstiffened in tension + stiffened in compression + no


157/205

Unstiffened in tension + stiffened in compression + no

shear influence

bcCd,

min,

o e o n s

Plate failure

End-plate/column flange thicknessyubffdt /36,0

157


158/205

Hollow Section Joints

158

9 General

a ure mo es


159/205

9 Example CHS members Range of validity

9 Worked examples

9 CIDECT materials

159

Web Desi n

tubular shape is popular due to its excellent

geometrical properties in compression and


160/205

making it ideal for use as columns

160

because of their hollow centre

they can be easily filled with concrete

good ductile properties and

ue o e con nemen e ec , concre e


161/205

cannot split away even if ultimate strengthis reached

161

Why the fuss about Hollow Section


162/205

Hollow Section Joints can be very flexible!

-the member design stage

162

Failure Modes for Welded Hollow


163/205

Mode B: Punching shearfailure of the chord face

the chord face

Mode D: Local bucklin of

Mo e C:Tension failure of

the web member

the web member

163

Failure Modes for Welded Hollow Section


164/205

Mode E: Overall shear

Mode F: Local buckling ofthe chord walls

Mode G: Local bucklin ofthe chord face

164

Tip: Minimize the number of Joints (and


165/205

Warren Trusses are a popular way tom n m ze e num er o mem ers an

joints165

Some Golden Rules to Avoid Tubular JointProblems


166/205

General Tips for Designers166

Weldin of Rectan ular Hollow Sections


167/205

167

Welding in Cold-Formed Zones- restriction at corner regions

May be carried out within a length 5 teither side of a cold-formed zone only if:

Cold-formed zones are normalized after cold-forming but before welding


168/205

-

Table 4.2 EN1993-1-8

r / t

ax mum c ness mm

Fully killed Aluminium-killed steel(Al 0,02 %)

25 10

any

any

, 2,0 1,5

12

10

,

168

Some Golden Rules to Avoid Tubular Joint

General tips for designers Width Ratios


169/205

169

Some Golden Rules to Avoid TubularJoint Problems

Wall Slenderness Web Angles


170/205

170

Ga ed vs. Overla ed Truss Joints Design tips to optimize welded HSS joint design

Select relatively thin branch

Consider virtues of a ed K-connections

G dOverlapped


171/205

Gapped

Easier and chea er to Hi her static and fati uefabricate strength, generally

Produces stiffer truss

re uces russ e ec ons

171

General

Chapter 7 of EN 1993-1-8

Background CIDECT materials Uni-planar and multi-planar joints

rcu ar, square or rec angu ar o ow sec ons

+


172/205

-

Combinations of hollow sections with open sections

Detailed application rules to determine the static resistancesof joints in lattice structures

172


173/205

on on on

T joint X joint Y joint

173

Geometrical Types of ComplexJoints

DK i t KK i t


174/205

DK oint KK oint

X oint T oint

DY joint XX joint

174

ec angua rcuar or s o or

------

failure


175/205

ordfac

C

l

sidewal

ilure

Chordfa

175

hear

e


176/205

hre

Chordfailu

r

-------ngshea

Punch

176

-

lure


177/205

i

Bracef

buckling

Local

177

Circular Hollow Section Joints

Tube model for chord face failure


178/205

178


Model for punching shear failure


179/205

179


Model for chord shear

gap


180/205

180

Rectan ular Hollow Section Joints

Analytical plastic lines model for chord face failure

or o n s o ype , or


181/205

ModelY joint

181


Model of the brace effective width

Model of chord shear failure


182/205

182


Model for the plastification or the local buckling

o e a era c or s e wa s


183/205

183

Joints between Hollow and OpenSection Members

Model of the brace effective width

Distribution of the stresses and deformationsat the end of a RHS member


184/205

184

Joints between Hollowan pen ec on em ers Model of chord shear failure

Shear of the chord in a K joint with gap


185/205

185

Joints between Hollowand Open Section Members

Model of the local plastification of the chord web


186/205

186

-

For welded oints between CHS brace members

and CHS chords

0,2 di / d0 1,0

Class 2 and 10 d / t 50 generally


187/205

Class 2 and 10 d0 / t0 50 generally

but 10 d0 / t0 40 for X joints

Class 2 and 10 di

/ ti 50

g

ov

g t1 + t2

187

Welded joints between CHS Membersin Uniplanar joints

Brace member connections sub ect to combined bendin and

axial force should satisfy

1,0,,,,, +

+ EdiopEdiipEdi

MM

N

N

,,,,,


188/205

M the desi n in- lane moment resistance, in table;, ,

Mip,i,Ed the design in-plane internal acting moment;M the design out-of-plane moment resistance, in, ,table;

Mo i Ed the design out-of-plane internal acting moment.

188

., .

Construction metalliqueet mixte acier-beton,

Tome 2, Conception et

mise en oeuvre, Editions

, ,


189/205

Paris, 1996. Ce0,9

1,0d0

0,7

0,81

p

11y

oyo

T

1y1

Rd1

tf

tC

fA

N

=

sin

.

10

1

poyoRd.1ktf

CN

=

0,4

0,5

,

30

20

15111y1y1

sintf

0,1

0,2

0,3

50

40

0,0

1,00,90,80,70,60,50,40,30,20,10,0

189

ec e russ o n , agona s an c or nangle 45and gap 20 mm. Chord is carrying force N0.Sd =

1363 6 kN and dia onals 580 kN. Steel S355.

hN1.Sd


190/205

b1=150

h1=15

0 h2=150

N2.Sd

t1=6g45

?45?

t0=8

h0=200

1363542,8

b0=200e=+20

190

Ran e of Validit

For excentricity

mmmmheh

5020025,02025,055,0 00

=

For diagonals

b Ebt yft

,


191/205

t

35150

yf

210000150

For chord

3556,

0,2b

5,00

0 35t0

0 35t0

0 25t0

00 +

0,2200

5,0 358

358

258

191

Chord shear failure


192/205

Punching shear failure

Brace failure

192

The diagonal resistance

k

bm

hbftN

n

m

i

m

iy

Rd

1

2sin

9,8 112

0

.1=

+

=


193/205

kN8,5941

5,12902,01501501501503558

9,82

=

+++

=

,

Factor kn = 0,902 expresses the reduction due to shear force

193

Gaphhh sin +

222eg

2121 sinsinsinsin=

+=

mm92745245245452

20 ,sinsinsinsin

=

+=


194/205

45245245452 sinsinsinsin

ear area

( ) ( ) 2000 35868200241,020022 mmtbhAv =+=+=

fAyv 135535861

The resistance

Rd ,15,145sin3sin3 M5.1

===

194

The diagonal resistance

bbhft

Nep

y

Rd

1

sin

2

sin3 M51

10

.1=

++=

kN9,2781151

6015045i

=

++=


195/205

,15,145sin45sin3

The effective width

1

0

01 15060200

81501010bmmmm

b

tbbep

==

==

195

or e ec ve w

1

2

110

0

2

0115080

3556200

35581501010bmmmm

ftb

ftbb

y

y

eff==

==


196/205

is the dia onal resistance

1==

( ) kN

effyRd

2,9371

801506415023556

M5

1111.1

=++=

,

196

Chord face failure 594,8 kN

Chord shear failure 903,8 kN

Punching shear failure 1278,9 kN


197/205

Punching shear failure 1278,9 kN

Brace failure 937,2 kN

,

acting forces in both diagonals (580 kN). OK

197

Worked Example - Gusset PlateConnecton

Connect TR 200 200 6,3 by plate P15. Force FSd=150 kN.

Steel S355J2H. Bolts M 8.8.


198/205

198

Plate

=

M1

200

,b

t = 6,30

h = 2001

20075015

=N

00

N 00


199/205

200750200

,, b = 2000h = 2000

Chord

0,2b

h5,0

0

0 35t

b

0

0 300

0 t

h25

0

00 +t

hb

0,2200

2005,0 35731

36

200 = ,,

2546336

200200 =+ ,,

3573136

200 = ,,

199

t = 151N1

= m1

h = 2001

t = 6,30

N = - 300 kNM0

0N M00

b = 2000h = 2000


200/205

Additional factors01 ===

1=mk

26003552262

0006

3557454

000300

1

111

1100

0

00

00,

,

,)

fW

M

fA

N(

,n

,y

Sd,

,y

Sd,jM =

+

=+=

012600131131 ,),(,)n(,km == 200

Desi n Check

M = 6 kNm1

t = 151N1 h = 2001

t = 6,30

N = - 300 kNM0

0N M00

b = 2000h = 2000


201/205

2

( )=+

=

MjM001

01

00

1

11142

1

,kb/t

b/tN

m

,y

Rd.

( ) 077900111

11200151412

200151

35536 2

1,

,,

,k/

/

,N

mRd.=

+

=

SdRd.Rd.,plM,,,hN,M === 797200077905050

111

201

CIDECT Materials

Wardenier J., Kurobane Y., Parker J.A.Dutta D., Yeomans N.: Design guide for

circu ar o ow section (CHS) joints

under predominantly static loading,

steel sections, Verlag TUV Rheinland


202/205

Gmbh, Kln, 1991.

Wardenier J., Dutta D., Yeomans N.

Parker J.A., Bucak O.: Design Guide for

Mechanical Applications, CIDECTT,

Construction with hollow steel sections,

Verlag TUV Rheinland Gmbh, Kln,1995.

202

-Tension

Check the end plate connection of CHS loaded in tension;force NSd=450 kN. Steel S235.

Based on CIDECT materials.

e1=51

NSdd0=168e2=


203/205

t0=5 tp =20

8 x M20 - 8.8

NSd

203

-

N 15,145000022

mmff

y

p,

30,52353

=

=

Shape factor f3 is taken form graph


204/205

Souinitel

8for ratio on exes x of graph

,3=

4

6

617,05168

00 =

=

td

2

e2td

td

100

00

+-

-

100

0.0 0.2 0.4 0.6 0.8 1.0

204

-

kNfA

B ubSRdt

7,121451

8002459,09,0.

===

asked number of bolts

311

145000011

1

NSd


205/205

73,711

145000011

1 = +=

+N

n Sd

135

ln30,5,,

ln,

2

1

3

3.

r

fRdt

1, 2

mmedr 1865121685,025,0101

=+=+=

mmedr 135511685,05,0102 =+=+=

205

structural connections

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