Use of active earth pressure for retaining wall design.
Use of active earth pressure for retaining wall design.
(OP)
I recently reviewed a cantilever retaining wall design. It occurred to me that the use of active soil pressure behind the wall is less conservative than using the at-rest soil pressure. Is this common practice? A model of the wall calculates a deflection of 1/16". It doesn't seem like this amount of movement really transitions the soil pressure from at-rest to active. Any thoughts are appreciated.





RE: Use of active earth pressure for retaining wall design.
RE: Use of active earth pressure for retaining wall design.
a) Adequately resist the at-rest earth pressures without undergoing enough deflection to consider active earth pressures
or
b) Deflect to the point where active earth pressures are achieved
For the strength of the wall itself I think using active pressures is fine, but for overturning and global stability using at-rest pressures would be prudent to make sure the wall deflects at the steam and does not rotate around the toe.
RE: Use of active earth pressure for retaining wall design.
RE: Use of active earth pressure for retaining wall design.
There are situations when you should consider earth pressure between Active and At Rest states. These include when the retaining wall is on closely spaced piles(soil arching is restricted), when you are on rock foundation(rotation about the toe is limited) and when you are designing hydraulic and U framed structures (they are more rigid). I have yet to come across a situation where you needed to use At rest earth pressure for cantilever retaining wall design.
http://www.soilstructure.com/
RE: Use of active earth pressure for retaining wall design.
RE: Use of active earth pressure for retaining wall design.
What have been some of your experiences? Have you found pressures to be higher or lower than expected? Or both?
RE: Use of active earth pressure for retaining wall design.
RE: Use of active earth pressure for retaining wall design.
Good info. Thanks!
RE: Use of active earth pressure for retaining wall design.