----- Original Message -----From: Joe VenutiSent: Thursday, November 03, 2011 9:33 AMSubject: Concrete Pedistal large
I am designing an entry toward structure for a large box store like use to be a Circuit City store. We have arch pedestals that are 6'-4" x 4'-4" x 4'-0" high. We designed this shape as a 12" thk concrete walls around the outside perimeter. I have #4's @ 18" each face for the walls. I have braced frames sitting on top of 2 sides. Below the frame columns are 18"sq columns w/4-#8's & #3 ties @ 8"oc.
The contractor wants to pour the whole volume as solid conc. in one pour and only use the rebar as designed for the walls around the perimeter. I have not designed any concrete above ground like this before.
Any comments or area to watch out for would be much appreciated. Admixtures for conc. Additional steel etc.
Harold I need to tap into vast knowledge and experience relating to concrete.
P.O. Box 5098
La Quinta, CA
Thursday, November 3, 2011
Re: Concrete Pedistal large
This sounds a lot like dozens of pump foundations that I have seen or designed in the past. Generally, they have been solid concrete and the reinforcing I have seen or used has been #5 @ 12 each way on the exposed faces. Once or twice I've seen other engineers use reinforcing on the underside as well; but I don't think that is necessary. I think I might be inclined to use 8 #6 instead of 4 #8 for the columns. I have never had, or heard of problems with concrete over heating for this size of pour; but in hotter climates that might be a consideration.
H. Daryl Richardson
at 9:01 AM