Shallow Post Foundation Design ASAE 486 1

[Splitrings]

Is anyone familiar with this document? We use this design procedure for posts for agricultural type pole buildings. Typically we design the posts as unconstrained without collars. This case is pretty straight forward. The problem I am having is the case of an unconstrained post with a concrete collar. There is a set of three formulas for this case. It is an iterative process to come to a solution. I have spent several days and I can't make it work. The equation is suppose to reduce to the case without a collar when tc & w are set to zero. I can't make this work either. Is there an error in this equation?

 

[Polecat]

Check out the Florida Building Code 2004 section 1819.7. It has formulas for both constrained and unconstrained pole embedments, plus a table of allowable soil pressures. If lateral deflection is not a problem, you can double the tabulated pressures.

There is also a spreadsheet developed by Daniel T. Li that will do exactly what you want, using those same formulas.

http://www.engineering-international.com/

http://www.spiraleng.com