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
----- Original Message -----
From: Joe Venuti
Sent: Thursday, November 03, 2011 9:33 AM
Subject: Concrete Pedistal large

Hello all


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.



Joe Venuti

Joven Engineering

P.O. Box 5098

La Quinta,  CA

760 408-6441