To: SEAOC Listservice <seaint(--nospam--at)seaint.org>
Subject: RE: old joist
From: Roger Turk <73527.1356(--nospam--at)compuserve.com>
Date: Thu, 27 Apr 2000 12:32:30 -0400
>From SJI's "Standard Specifications and Load Tables," 1978:
Based on 30 ksi *allowable* stress a parallel chord 32LH07 (self weight: 20
plf) with a 60 ft span has a TOTAL LOAD capacity of 262 plf, or for LIVE LOAD
deflection limited to L/360, a LIVE LOAD capacity of 133 plf. Multiply L/360
load by 1.5 to get the LIVE LOAD that produces a deflection of L/240. Holes
in top and bottom chords reduce load capacity.
Web design requirements are:
"The vertical shears to be used in the design of the web members shall be
determined from full uniform loading but such vertical shear shall not be
less than 25 percent of the end reaction.
Interior vertical web members used in modified Warren type web systems shall
be designed to resist the gravity loads supported by the member plus 1/2 of
1.0 percent of the top chord axial force."
Hope this helps.
A. Roger Turk, P.E.(Structural)
Brian Smith wrote:
>> Can anyone give me the allowable loads for '78 vintage 32LH07's, 60'
span???? Also, did the SJI LH spec at that time require a minimum shear at
midspan like they do with the K's now???<<