Design of shallow circular foundation 1

[jeg1976]

Can anyone point me to a good reference for the design of shallow circular (cylindrical) foundations? This is pretty much like a Sonotube-type foundation. This would be a new foundation where a hole is drilled into an existing grade slab (4 inch thick), the earth is dug out up to 4 feet below grade, the reinforcement is installed, and then the concrete is poured in the hole. The foundation would also have to take moment. Thanks in advance.

 

[BAretired]

Four feet below grade? How do you expect to develop any moment with that? What magnitude of load and moment do you expect to achieve with this construction? Do you have frost in your area? Are you prepared to accept frost heave?

I don't know of any good reference for that type of foundation. I doubt that there is one. Why are you doing this? Is the existing slab moving and in need of additional support?

BA

 

[TLHS]

You aren't going to get a lot of strength out of four feet, but the IBC has provisions for determining the lateral resistance of post foundations.

I don't have a current copy with me, but in the 2000 version it was "1805.7 Designs employing lateral bearing"

 

[briancpotter]

ASAE has a publication on shallow post foundation design. It can be found here:

http://bse.wisc.edu/Bohnhoff/Publications/Copyrighted/EP486_1.pdf

Brian C Potter, PE
Simple Supports - The history and practice of structural engineering.
ConstructionPic - Send annotated jobsite photos.

 

[dhengr]

Brian:
Thanks a million, very interesting std.