Page 479 - Shigley's Mechanical Engineering Design

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454 Mechanical Engineering Design
F/2 is transmitted by each of the splice plates, but since the areas of the splice
plates are half those of the center bars, the stresses associated with the plates are the
same. So for stresses associated with the plates, the force and areas used will be those
of the center plates.

Bearing in bolts, all bolts loaded:

F S p
σ = =
2td n d
3

2(1) 85
2tdS p 4
F = = = 85 kip
n d 1.5
Bearing in members, all bolts active:
F (S y ) mem
σ = =
2td n d
3

2td(S y ) mem 2(1) 4 54
F = = = 54 kip
n d 1.5
Shear of bolt, all bolts active: If the bolt threads do not extend into the shear planes
for four shanks:
F S p
τ = = 0.577
2
4πd /4 n d
85
S p
F = 0.577πd 2 = 0.577π(0.75) 2 = 57.8 kip
n d 1.5
If the bolt threads extend into a shear plane:
F S p
τ = = 0.577
4A r n d
0.577(4)A r S p 0.577(4)0.351(85)
F = = = 45.9 kip
n d 1.5
Edge shearing of member at two margin bolts: From Fig. 8–25,

F 0.577(S y ) mem
τ = =
4at n d
4at0.577(S y ) mem 4(1.125)(1)0.577(54)
F = = = 93.5 kip
n d 1.5
Tensile yielding of members across bolt holes:
F (S y ) mem
=
4 − 2 4 t n d
σ = 3
3
3
4 − 2 t(S y ) mem 4 − 2 (1)54

F = 4 = 4 = 90 kip
n d 1.5