Page 96 - 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 81

Since > 1, use 1, and the design tension strength is
0.5 2
T 40.6 a b 1.69 7.83 kips 6.67 kips, ok
d 1.48
1
The / -in end plate is ok.
2
Column web. The column web sees a transverse force of 80 kips.
Figure 2.14d shows a yield-line analysis (Anand and Bertz, 1981) of the
column web. The normal force ultimate strength of the yield pattern
shown is
2T l
P 8m e 1 f
u p BT 2 g 2sT 2 gd
2
2
where m 1/4 F t . For the present problem, m 0.25 50 (0.44)
p y w p
2.42 kips-in/in, T 11.25 in g 5.5 in and l 15 in so
2 3 11.25 15
5 8 3 2.42 a 1 b 5 63.5 kips
P u
Bs11.25 2 5.5d 2s11.25 2 5.5d
Thus P 0.9 63.5 57.2 kips 80 kips, no good, and the column
u
web is unable to sustain the horizontal force from the gusset without
stiffening or a column web-doubler plate. Figure 2.15 shows a possible
stiffening arrangement.
It should be noted that the yield-line pattern of Fig. 2.14d compro-
mises the foregoing end plate/prying action calculation. That analysis
assumed double curvature with a prying force at the toes of the end plate
a distance a from the bolt lines. But the column web will bend away as
shown in Fig. 2.14d and the prying force will not develop. Thus, single
curvature bending in the end plate must be assumed, and the required
end plate thickness is given by AISC, 2005, p. 9–10.

4.44Tbr 4.44 3 6.67 3 2.12
t 5 5 0.600 in
req B pF u B 3 3 58
5
and a / -in-thick end plate is required.
8
Gusset to beam. The weld is already designed. The beam must be
checked for web yield and crippling, and web shear.
Web yield. R 10 0.305 50 (32 2.5 1.12) 531 kips >
wy
132 kips, ok
Web crippling.
32 0.305 1.5 50 329000 30.530
2
R 0.75 0.8 0.305 c11 a ba b d
wcp 13.7 0.530 B 0.305
179 kips > 132 kips, ok

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