Page 83 - Handbook of Structural Steel Connection Design and Details

Design of Connections for Axial, Moment, and Shear Forces

68 Chapter Two

(3) Web shear:

P 1.0 0.6 50 0.47 24.1 340 kips > 282 kips, ok
v
The maximum shear due to the couple is centered on the
gusset 15 in from the beam end. It does not reach the beam-
to-column connection where the beam shear is 170 kips.
Because of the total vertical shear capacity of the beam and the
gusset acting together, there is no need to check the beam web
for a combined shear of V and R of 282 170 452 kips.
s
4. Beam-to-column connection: The shear load is 170 kips and the axial
force is H / A 218 / 150 kips. Since the W18 50 is a col-
c
lector, it adds load to the bracing system. Thus, the axial load is 218
150 368 kips. However, the AISC book on connections (AISC, 1992)
addresses this situation and states that because of frame action (dis-
tortion), which will always tend to reduce H , it is reasonable to use
C
the larger of Hc and A as the axial force. Thus the axial load would
be 218 kips in this case. It should be noted however that when the
brace load is not due to primarily lateral loads frame action might
not occur.
a. Bolts and end plate: Though loads caused by wind and seismic
forces are not considered cyclic (fatigue) loads and bolts in tension
are not required to be designed as slip critical, the bolts are spec-
ified to be designed as A490 SC-B-X 1-in diameter to accommodate
1
the use of oversize 1 / 4-in-diameter holes. As mentioned earlier
the slip-critical strength criterion in used. Thus, for shear
r 26.2 kips/bolt
v
and for tension

r 66.6 kips/bolt
t
3
The end plate is / 4 in thick with seven rows and 2 columns of
1
bolts. Note that the end plate is 14 / 2 in wide for the gusset to
1
column connection and 8 / in wide for the beam-to-column
2
connection.
For shear
R 26.2 14 367 kips > 170 kips, ok
v
For tenion
R 66.6 14 932 kips > 218 kips, ok
t
Bolt bearing and tearout need not be checked because the slip
critical strength limit state has been used.

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