Need a book? Engineering books recommendations...
Re: Steel Joists[Subject Prev][Subject Next][Thread Prev][Thread Next]
- To: seaint(--nospam--at)seaint.org
- Subject: Re: Steel Joists
- From: Phil Hodge <phil(--nospam--at)joistdesign.com>
- Date: Mon, 04 Jan 1999 19:53:33 -0500
A 60DLH12 x 88'0 should be capable of safely supporting a total load of 31,100#, distributed uniformly across the top chord. While Jim's comment about pitch over 1/8:foot is correct, any joist with an SJI designation should be capable of supporting the SJI tabular load.
As for the actual safe load, today, good luck. The only way will be to measure actual member and weld sizes, and resurect your statics skills. Be careful measuring, angle thicknesses are not necessarily multiples of 1/16" - scrape the paint and use a micrometer. And of course watch out for rust. The steel was probably A36 mod 50, but some fabricators still used straight A36. And one piece of angle might be different steel from the one right next to it in the joist. When I measure a joist from this time period I look at each member, and if Fy=36 would work for the stated load, I assume that is what it is. If 36 doesn't work, but 50 ksi does, then I assume it is 50. The welds were probably all made with E70 wire. Not guaranteed correct, but reasonable based on my experience. And it's not practical to cut coupons from every web member and check it.
If you can find actual shop drawings, obviously your job just got a lot easier, but don't hold your breath. Haven-Busch may have furnished them, but Ceco never did, and I don't think Sheffield did.
Michael D Zaitz wrote:
I have a project where I am evaluating some existing framing. We have a
copy of the original building plans and they were done in 1966. The
joists over a pool area are called out on the plan as:
Special Deep Joists at 5'-10" o.c.
(48" deep at brg., 60" deep at midspan)
These members are spanning approximately 88 feet and are not listed in
the 50 year Steel Joist Digest. I was wondering if anyone out there may
have information on these joists? The project is in Columbus, GA for
Columbus State University.
- Steel Joists
- From: Michael D Zaitz
- Steel Joists
- Prev by Subject: Re: Steel Joists
- Next by Subject: Still shear-off bolted connections
- Previous by thread: Re: Steel Joists
- Next by thread: ASCE Forensic Engineering January 12 Meeting