D E –
It’s not a uniform pressure; it’s a trapezoidal pressure.
I’ve been doing this a long time. Don’t worry; the numbers are right.
Regards,
T. William (Bill) Allen, S.E.
Consulting Structural Engineers
V (949) 248-8588 •
-----Original Message-----
From: D E [mailto:struktur.dle@gmail.com]
Sent: Thursday, May 29, 2008 1:37 PM
To: seaint@seaint.org
Subject: Re: Protection of Drain Pipe Under Mat Foundation
Sounds like your soils allowables are close to, if not over, the limit. I just wanted to point out that a 29'x22.5' map with a 700psf soil pressure gives a weight of cmu of 29'x22.5'x700psf=456,000 lbs of masonry. That is a lot of masonry. The 1300psf under lateral seems really high too. Things to check: What is your weight of masonry? What is the vertical center of gravity of cmu? what is your allowable base shear coefficient?