Need a book? Engineering books recommendations...
Live load reduction and load combinations[Subject Prev][Subject Next][Thread Prev][Thread Next]
- To: <seaint(--nospam--at)seaint.org>
- Subject: Live load reduction and load combinations
- From: "Bruce Holcomb" <bholcomb(--nospam--at)brpae.com>
- Date: Tue, 21 Dec 2004 14:20:05 -0600
Title: Live load reduction and load combinations
I just had a discussion with a co-worker and want to be sure of how I am designing. I am designing an interior footing supporting a column with a large tributary area (2000 sq. ft.). My reduced floor live load is 50% of the unreduced live load (100 psf in a non-assembly area). I am using a reduced roof live load of 12 psf. When I check Dead + Live + Roof Live, my load combination is D+3/4(L+Lr). I am checking other combinations too, such as D+3/4(L+S). I’m using IBC 2003.
My question is, can I apply the ¾ load combination factor on the reduced floor live load and the reduced roof live load (or snow load)? My co-worker says that I am effectively using less than the minimum reduced live load which is 50% of the unreduced live load (3/4*0.5*L=0.375*L). But the way I read it, these are two separate issues and I am not violating the code. First, you calculate the reduced live load, checking the maximum reduction, then you put that load in the load combinations and design the footing for the result.
I may simply be having a brain-lapse, so please be kind… I also have had a lot of sugar… cookies, cakes, etc., even a honey baked ham today!
Bruce D. Holcomb, P.E., S.E.
Member AISC, SEAKM
Butler, Rosenbury & Partners
300 S. Jefferson, Suite 505
Springfield, MO 65806
Architecture, Engineering, Interior Design, Planning & Development
Your Vision. Our Focus.
- Prev by Subject: Re: Live load / occupancy correlation
- Next by Subject: RE: Live load reduction and load combinations
- Previous by thread: RE: AWWA D100
- Next by thread: RE: Live load reduction and load combinations