Page 138 - Handbook of Structural Steel Connection Design and Details

Design of Connections for Axial, Moment, and Shear Forces

Design of Connections for Axial, Moment, and Shear Forces 123

Tearout between bolts will not control in this case since 3 0.9375
2.0625 > 1.281 or 1.031.
From the above, the shear/bearing/tearout strength of the flange
connection is

R 2 27.1 2 2 26.9 2 2 27.1 2
vpt
324 kips > 311 kips, ok

In the expression for R , the first term is for the two bolts in the
vpt
center, which are controlled by shear; the second term is for the outer
two bolts controlled by outer plate edge distance; and the third term
is for the two inner bolts again controlled by bolt shear.
This completes the calculation for the flange portion of the splice.
The bolts, outer plate, and inner plates, as chosen above, are ok.

B. Web connection:
The calculations for the web connection involve the same limit states
as the flange connection, except for chord net section, which involves
flanges and web.
1. Member limit states:
a. Bolts: A bolt pattern is required to check the web.
178
Number required 5 3.28
2 3 27.1
Try four bolts.
b. Bearing/tearout: This will be checked after the web splice plates
are designed.
c. Block shear fracture: Assume the bolts have a 3-in pitch
longitudinally.

A (4.75 1.5 1) 0.440 2 2.86 in 2
nv
A (3 1 1) 0.440 0.88
nt
A 4.75 0.440 2 4.18 in 2
gv
A 3 0.440 1.32 in 2
gt
F A 65 0.88 57.2 kips
u nt
0.6F A 0.6 65 2.86 112 kips
u nv
0.6F A 0.6 50 4.18 125 kips
y gy
U 1.0
bs
R 0.75[57.2 min{115,125}] 127 kips 178 kips, no
bs
good

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