Page 309 - Handbook of Structural Steel Connection Design and Details

Partially Restrained Connections

294 Chapter Four

6. Check bolt bearing on the beam flange:

F bearing 5 N bolts s R n d 5 s10ds0.75 3 102d 5 767 kips ok

7. Check bolt service load slip capacity:

M slip 5 s10 boltsds10.2 kip/boltds20.99 ind
5 2141 kip-in . 1.25 M 5 2100 kip-in

8. Check block shear: Assume shear failure along the bolts and tensile failure
across bolt gage and U 1.0:
bs
1
A 2 a16.5 2 4 2 b (0.75) 18.00 in 2
gv 2
A (5)(0.75) 3.75 in 2
gt
A 18.00 – 2(3.5 1) (0.75) 12.75 in 2
nv
A 3.75 2 (1 0.75) 2.25 in 2
nt
R n 5 0.6 F u A nv 1 U bs Fu A nt # 0.6 F y A gn 1 U bs F u A nt
5 0.6s65ds12.75d 1 s1.0ds65ds2.25d # 0.6s50ds18.00d
1 s1.0ds65ds2.25d
5 643.5 kips # 686.2.7 kips
R n 5 s0.75d643.5 kips 5 482.6 kips

9. Determine weld size: The weld thickness, based on a 70-ksi electrode is

F plate
t
weld
0.6 F Exx 3 b p
267.3 kips
5 0.67 in,
0.6 3 70 ksi 3 9.5 in
say 3/4 in (use full-penetration weld)
10. Detail the shear connection to the web: The design of the shear connec-
tion for this case will not be carried out in detail here (see Chap. 2 for
design of shear connections). From the AISC Manual, Part II, a 5/16-in
7
pair of angles with 4 / 8 in A325X bolts provide 137 kips of shear resis-
tance. This is larger than the 75 kips required for design. The final design
is shown in Fig. 4.10.
11. Moment and rotation at service: The connection will not slip until the fric-
tional capacity of the bolts (M ) is reached when the force in the plate
slip
reaches approximately 102 kips. This corresponds to a stress:
102 kips
s slip 5 5 14.3 ksi
9.5 3 0.75

Downloaded from Digital Engineering Library @ McGraw-Hill (www.accessengineeringlibrary.com)
Copyright © 2009 The McGraw-Hill Companies. All rights reserved.
Any use is subject to the Terms of Use as given at the website.