L11 Bolt Connection.pdf

7/28/2019 L11 Bolt Connection.pdf

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Timber and Steel DesignTimber and Steel Design

Riveted Connections

Types of Joints

Failure of Joints

Bearing & Friction connections

Truss Joints Shear and Tension on Bolt

Mongkol JIRAVACHARADET

S U R A N A R E E INSTITUTE OF ENGINEERING

UNIVERSITY OF TECHNOLOGY SCHOOL OF CIVIL ENGINEERING

LectureLecture 1111 BoltedBolted ConnectionsConnections

Riveted Connections

rivet = round ductile steel bar (shank) with a head at one end

Snap

d

Pan Flat

countersunk

Round

countersunk

d= Shank diameter

= Nominal diameter


2/33

Riveting Procedure

Rivets are heated before driving

hot rivet = hole

Head is formed by

- Hand hammer

- Hydraulic pressure

- Pneumatic pressure

On cooling, the rivet shrinks both length

and diameter

Connected parts become tighter:

- Tension in rivet

- Compression in plates

Friction between plates called

clamping action


3/33

Forms of riveted joints

Lap Joint P

P

P

P

Rivet in single shear

fv= P/ A

P

P

e

Eccentricity in lap joint

PP

Undesired bending causes tension in rivetsDouble riveted lap joint


4/33

Butt JointP

P

- F

Butt joint v.s. Lap joint:

P

P/2

P/2

Rivet in double shear

fv= P/2A

P/2P/2

- FF

- F F

Bolted ConnectionsBolted Connections


5/33

FFFF

P

P/2

P/2

W section

(a) F (b)F

(d)F(c)F

(e)F (f)F


6/33

Failure of Joints

PP

Single shear in lap joint

P/2P

Double-shear in butt joint

P/2

Case 1: Shear failure of rivets

Shear stress in rivet exceed the limit

Case 2: Shear failure of plates

Shearing out

Insufficient edge distance

P P

Case 3: Tension or Tearing failure of plates

Tensile stress at net cross section exceeds tensile strength

Case 4: Bearing failure of plate

P P

Plate may be crushed when bearing stress in plate exceeds the limit


7/33

Bolted Connections

Beam splice moment connection

P

P/2

P/2

Friction from clamping pressure

using high strength bolt

BearingBearing--type Connectionstype Connectionsd

F

Ft (../.2)

FFv (../.2)

Shearing Strength: vFd2)4/(

Friction-type Bearing-type

A307 1,400 - 700

A325 (F) 3,100 1,200 1,480

A325 (FF) 3,100 1,200 2,100

A490 (F) 3,800 1,480 1,970

A490 (FF) 3,800 1,480 2,800


8/33

Threads Excluded from Shear Plane or not ?Threads Excluded from Shear Plane or not ?

Bearing

stress

2P

P

P

Diameter = dShear

planes

Bearing StrengthBearing Strength

For long-slotted holes perpendicular to the load Fp = 1.0 Fu

1.22

e up u

L FF F

d= forLe < 1.5d

d

t

Bearing area = dx t

Excessive bearing results in shear tear-out failure mode.

Failure surface

Failure surface

Ra

Ra/2

Ra/2

Le

ppa FtdFR == areabearing

Allowable bearing strength Ra :

For standard or short-slotted holes Fp = 1.2 Fu

uuea FtdFtLR 2.15.0 =

uuca FtdFtLR 2.16.0Or =


9/33

Spacing and EdgeSpacing and Edge--Distances RequirementsDistances Requirements

Pitch: center-to-center of bolts parallel to axis of member

Gage: center-to-center of bolts lines perpendicular to axis of member

Edge distance: shortest distance from center of bolt to edge

min Le = 1.5-2 diameter

Distance between bolts: shortest distance between bolts

min distance = 3 diameter A490

A325

Marking for Bolt

A307

P Pg

s s


12

Lc2 Lc1

Le s

Lc= clear distance, in the direction

parallel to the applied load.

Le = edge-distance to center of the hole

s = center-to-center spacing of holes

h = d+ 2 mm = hole diameter

For edge bolts(2), use Lc= Le h/2

For other bolts(1), use Lc= s h

)2-(1.5J3.4TableAISCfromvalue

)3y(preferabl2 32

ddL

dds

e


10/33


11/33

F 11-1F P A36, A325 22 .., , , 1.5d, 3d

PP

22 mm. bolts

1.0 cm1.0 cm

P P30 cm

F:

Ag = 1.0 (30) = 30.2

An = 30 2 (2.5) (1.0) = 25 .2 = AeP = 0.60 (2.5) (30.0) = 45

P = 0.50 (4.0) (25.0) = 50

F:

: P = 0.25 (2.2) 2 (2.1) (4) = 31.93

: P = (1.0) (2.2) (1.2) (4.0) (4) = 42.24

FP = 31.93

8 9 (F)

F 11-2 FF A325 19 .. ? F A36 FF

P/2= 40 tonP= 80 ton

19 mm. bolts (A = 2.84 cm2)

2.0 cm1.0 cm

P/2= 40 ton

1.0 cm

F:

= 2(2.84)(2.1) = 11.93 ()

= (2.0)(1.9)(1.2)(4.0) = 18.24

F = 80/11.93 = 7+


12/33

F 11-3 F V 80 F A325 22 .. (A=3.8 .2) F F A36

2 cm

W500x128

Ix = 71000

tf= 1.8

2 cm

48.8cm

45.2cm

PL2x40

PL2x40

s

I = 71,000 + 2(240)(25.4)2

= 174,226 .4

q = VQ/I

= (80)(240)(25.4)/174,226

= 0.93 /.

F = (2)(2.2)(1.8)(1.2)(4.0) = 38.02

s = 15.96/0.93 = 17 . ( 15 . c-c)

F = (2)(3.8)(2.100) = 15.96 ()

F S:

24 = 24(1.8) = 43.2 . > 15 . OK

478 478(1.8)

2,500

f

y

t

F= = 17.2 . > 15 . OK

Smax = 30 . > 15 . OK

AISC smax :

30 . FF

478/ yF 24


13/33

Slip-critical(Friction-type) Connections

F A325 A490

F ()

A490A325 (..)

15.912.71922.317.72229.123.22546.432.332

PP

P

P

N

N

F

F

AISC360-05 Specification for Structural Steel Buildings


14/33

d+ 2 ..d+ 8 ..

(d+ 2 ..) (d+ 10 ..)

(d+ 2 ..) 2.5 d

(F)

(F)

(F)

(F)

d+ 2 mm

(a) Standard

d+ 8 mm

(b) Oversized

d+ 10 mm

(c) Short slot

d+ 2 mm

2.5 d

(d) Long slot

d+ 2 mm

Gusset plate

F- F

- F Gusset plate


15/33

Truss Joint

Double member with a single connector piece, called a gusset plate.

Members must have sufficient "bite" into the plate for bolts or weld contact.

Converging centerlines enable equilibrium without member moments.

F F B A325 19 .. F F 12 ..

B

2Ls 75x75x10 2Ls 90x90x1028 ton

C20 ton

A

1L

50x5

0x8

D

8 ton

1L50x5

0x8

7 ton

E

A325 F

: Fv = 2,100 ./.2

: Fp

= 1.2(4,000) = 4,800 ./.2


16/33

Control2 22 2 1.9 2.1 11.91 ton4 4

vP d F = = =

AB: P = 20

2Ls 75x75x10 FF A325 19 .. 1

2 1.9 2(1.0) 4.8 18.24 tonpP d t F = = =

= 20/11.91 = 1.68 2

Control

BC: P = 28 2Ls 90x90x10 F

2 22 2 1.9 2.1 11.91 ton4 4

vP d F = = =F

2 1.9 2(1.0) 4.8 18.24 tonpP d t F = = =

= 28/11.91 = 2.53 3

Control

BD: P = 8 1Ls 50x50x8

2 21.9 2.1 5.95 ton4 4

vP d F

= = =F

1.9 0.8 4.8 7.30 tonpP d t F = = =

= 8/5.95 = 1.35 2

Control

BE: P = 7 1Ls 50x50x8

2 21.9 2.1 5.95 ton4 4

vP d F

= = =F

1.9 0.8 4.8 7.30 tonpP d t F = = =

= 7/5.95 = 1.18 2


17/33

B

D

CA

E

Gusset plate 20 mm

More ckeck for:

- Effective area of tension members (0.5FuAe)

- Block shear failure of tension members

2Ls 75x75x10 2Ls 90x90x10

1L

50x50x8

1L50x5

0x8

Bolt A32519 mm

Detail Drawing

Timber and Steel DesignTimber and Steel Design

Riveted Connections

Types of Joints

Failure of Joints

Bearing & Friction connections

Truss Joints

Shear and Tension on Bolt

Mongkol JIRAVACHARADET

S U R A N A R E E INSTITUTE OF ENGINEERING

UNIVERSITY OF TECHNOLOGY SCHOOL OF CIVIL ENGINEERING

LectureLecture 1111 BoltedBolted ConnectionsConnections


18/33

Riveted Connections

rivet = round ductile steel bar (shank) with a head at one end

Snap

d

Pan Flat

countersunk

Round

countersunk

d= Shank diameter= Nominal diameter

Riveting Procedure

Rivets are heated before driving

hot rivet = hole

Head is formed by

- Hand hammer

- Hydraulic pressure

- Pneumatic pressure


19/33

On cooling, the rivet shrinks both length

and diameter

Connected parts become tighter:

- Tension in rivet

- Compression in plates

Friction between plates calledclamping action

Forms of riveted joints


20/33

Lap Joint P

P

P

P

Rivet in single shear

fv= P/ A

P

P

e

Eccentricity in lap joint

P

P

Undesired bending causes tension in rivetsDouble riveted lap joint

Butt JointP

P

- F

Butt joint v.s. Lap joint:

P

P/2

P/2

Rivet in double shear

fv= P/2A

P/2P/2

- FF- F F


21/33

Bolted ConnectionsBolted Connections

FFFF

P

P/2

P/2

W section

(a) F (b)F

(d)F(c)F


22/33

(e)F (f)F

Failure of Joints

PP

Single shear in lap joint

P/2P

Double-shear in butt joint

P/2

Case 1: Shear failure of rivets

Shear stress in rivet exceed the limit

Case 2: Shear failure of plates

Shearing out

Insufficient edge distance


23/33

P P

Case 3: Tension or Tearing failure of plates

Tensile stress at net cross section exceeds tensile strength

Case 4: Bearing failure of plate

P P

Plate may be crushed when bearing stress in plate exceeds the limit

Bolted Connections

Beam splice moment connection

P

P/2

P/2

Friction from clamping pressure

using high strength bolt


24/33

BearingBearing--type Connectionstype Connectionsd

FFt (../.2)

FFv (../.2)

Shearing Strength: vFd2)4/(

Friction-type Bearing-type

A307 1,400 - 700

A325 (F) 3,100 1,200 1,480

A325 (FF) 3,100 1,200 2,100

A490 (F) 3,800 1,480 1,970

A490 (FF) 3,800 1,480 2,800

Threads Excluded from Shear Plane or not ?Threads Excluded from Shear Plane or not ?

Bearing

stress

2P

P

P

Diameter = dShear

planes


25/33

Bearing StrengthBearing Strength

For long-slotted holes perpendicular to the load Fp = 1.0 Fu

1.22

e up u

L FF F

d= forLe < 1.5d

d

t

Bearing area = dx t

Excessive bearing results in shear tear-out failure mode.

Failure surface

Failure surface

Ra

Ra/2

Ra/2

Le

ppa FtdFR == areabearing

Allowable bearing strength Ra :

For standard or short-slotted holes Fp = 1.2 Fu

uuea FtdFtLR 2.15.0=

uuca FtdFtLR 2.16.0Or =


Pitch: center-to-center of bolts parallel to axis of member

Gage: center-to-center of bolts lines perpendicular to axis of member

Edge distance: shortest distance from center of bolt to edge

min Le = 1.5-2 diameter

Distance between bolts: shortest distance between bolts

min distance = 3 diameter A490

A325

Marking for Bolt

A307

P Pg

s s


26/33


12

Lc2 Lc1

Le s

Lc= clear distance, in the direction

parallel to the applied load.

Le = edge-distance to center of the hole

s = center-to-center spacing of holes

h = d+ 2 mm = hole diameter

For edge bolts(2), use Lc= Le h/2

For other bolts(1), use Lc= s h

)2-(1.5J3.4TableAISCfromvalue

)3y(preferabl2 32

ddL

dds

e


27/33

F 11-1F P A36, A325 22 .., , , 1.5d, 3d

PP

22 mm. bolts

1.0 cm1.0 cm

P P30 cm

F:

Ag = 1.0 (30) = 30.2

An = 30 2 (2.5) (1.0) = 25 .2 = AeP = 0.60 (2.5) (30.0) = 45

P = 0.50 (4.0) (25.0) = 50

F:

: P = 0.25 (2.2) 2 (2.1) (4) = 31.93

: P = (1.0) (2.2) (1.2) (4.0) (4) = 42.24 FP = 31.93


28/33

8 9 (F)

F 11-2 FF A325 19 .. ? F A36 FF

P/2= 40 tonP= 80 ton

19 mm. bolts (A = 2.84 cm2)

2.0 cm1.0 cm

P/2= 40 ton

1.0 cm

F:

= 2(2.84)(2.1) = 11.93 ()

= (2.0)(1.9)(1.2)(4.0) = 18.24 F = 80/11.93 = 7+

F 11-3 F V 80 F A325 22 .. (A=3.8 .2) F F A36

2 cm

W500x128

Ix = 71000

tf= 1.8

2 cm

48.8cm

45.2cm

PL2x40

PL2x40

s

I = 71,000 + 2(240)(25.4)2

= 174,226 .4

q = VQ/I

= (80)(240)(25.4)/174,226

= 0.93 /.

F = (2)(2.2)(1.8)(1.2)(4.0) = 38.02

s = 15.96/0.93 = 17 . ( 15 . c-c)

F = (2)(3.8)(2.100) = 15.96 ()


29/33

F S:

24 = 24(1.8) = 43.2 . > 15 . OK

478 478(1.8)

2,500

f

y

t

F= = 17.2 . > 15 . OK

Smax

= 30 . > 15 . OK

AISC smax :

30 . FF

478/ yF 24

Slip-critical(Friction-type) Connections

F A325 A490

F ()

A490A325 (..)

15.912.71922.317.722

29.123.22546.432.332

P

P

P

P

N

N

F

F


30/33

AISC360-05 Specification for Structural Steel Buildings

d+ 2 ..d+ 8 ..

(d+ 2 ..) (d+ 10 ..)

(d+ 2 ..) 2.5 d

(F)(F)

(F)

(F)

d+ 2 mm

(a) Standard

d+ 8 mm

(b) Oversized

d+ 10 mm

(c) Short slot

d+ 2 mm

2.5 d

(d) Long slot

d+ 2 mm


31/33

Gusset plate

F

- F

- F Gusset plate

Truss Joint

Double member with a single connector piece, called a gusset plate.

Members must have sufficient "bite" into the plate for bolts or weld contact.

Converging centerlines enable equilibrium without member moments.


32/33

F F B A325 19 .. F F 12 ..

B

2Ls 75x75x10 2Ls 90x90x1028 ton

C20 ton

A

1L

50x50x8

D

8 ton

1L50x5

0x8

7 ton

E

A325 F

: Fv= 2,100 ./.2

: Fp

= 1.2(4,000) = 4,800 ./.2

Control2 22 2 1.9 2.1 11.91 ton4 4

vP d F

= = =

AB: P = 20

2Ls 75x75x10 FF A325 19 .. 1

2 1.9 2(1.0) 4.8 18.24 tonpP d t F = = =

= 20/11.91 = 1.68 2

Control

BC: P = 28 2Ls 90x90x10 F

2 22 2 1.9 2.1 11.91 ton4 4

vP d F

= = =F

2 1.9 2(1.0) 4.8 18.24 tonpP d t F = = =

= 28/11.91 = 2.53 3


33/33

Control

BD: P = 8 1Ls 50x50x8

2 21.9 2.1 5.95 ton4 4

vP d F

= = =F

1.9 0.8 4.8 7.30 tonpP d t F

= = =

= 8/5.95 = 1.35 2

Control

BE: P = 7 1Ls 50x50x8

2 21.9 2.1 5.95 ton4 4

vP d F

= = =F

1.9 0.8 4.8 7.30 tonpP d t F = = =

= 7/5.95 = 1.18 2

B

D

CA

E

Gusset plate 20 mm

More ckeck for:

- Effective area of tension members (0 5F A )

2Ls 75x75x10 2Ls 90x90x10

1L

50x50x8

1L50x50

x8Bolt A32519 mm

Detail Drawing

Documents

L11 Bolt Connection.pdf