Bill,
Similar to what Conrad posted, I’ve used 2% of the force that can be developed in the beam flange. Say you are bracing a W12x35, Fy = 50 ksi, you would design the bracing force, Pbr = 0.02 x 0.6 x 50ksi x 6.5” x 0.5” = 1.95 kips (ASD). I’ve kinda followed the ’89 ASD Spec E4 regarding lacing of built-up members (pg 5-44 of the green book). HTH
David A. Topete, SE
From: Conrad Harrison [mailto:sch.tectonic@bigpond.com]
Sent: Wednesday, October 03, 2007 5:46 PM
To:
Subject: RE: UBC 1630.8.2.2.1.7 Bracing Load
I don’t have the UBC but texts comparing various codes around the world indicate most codes usually adopt a value between 2% and 2.5% of the force in the critical flange.
Regards
B.Tech (mfg & mech), MIIE, gradTIEAust
mailto:sch.tectonic@bigpond.com
From: Bill Allen [mailto:T.W.Allen@cox.net]
Sent: Thursday, 4 October 2007 10:01
To:
Subject: UBC 1630.8.2.2.1.7 Bracing Load
In bracing the top and bottom flange of a steel beam, what force do I use to design the brace connection?
TIA,
T. William (Bill) Allen, S.E.
Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509