Regarding soil pressures for structural design of a foundation wall with backfill on both sides

[Geotech East Ontario]

This is not something I am currently dealing with, but was just a thought. If someone were to request professional recommendations for the soil pressures used for the structural design of a foundation wall that has backfilled soil present on both sides, what kind of comments or guidelines could be provided?

I understand that the moment from one side will be somewhat balanced by the fill on the other side, i.e., the passive pressure from one side may be able to balance out the active pressure from the other side, depending on the height of backfill on both sides and of course assuming that the passive pressure activates. Backfill on one side can resist the sliding and rotation caused due to backfill on the other side, but how should the wall be designed then? Hydrostatic pressures should be considered carefully. Could the wall overturn before it moves enough to engage the passive pressure? How should it be designed to remain conservative? Any thoughts will be appreciated.

Thanks in advance!

 

[EireChch]

If the fill is more or less at the same height then one side is not pushing against the other. it is not an earth pressure problem

 

[PEinc]

Diagram the wall and the forces - active soil pressure, passive soil pressure, live load and dead load surcharge pressures, and the building's shear force and moment. Then analyze for stability and bearing.

http://www.PeirceEngineering.com

 

[geotechguy1]

Is this not more or less the same as asking what the horizontal earth pressure is on a slice of soil? I wouldn't think it's something you actually need to design for though.

 

[SlideRuleEra]

This is not something I am currently dealing with, but... if someone were to request professional recommendations for... backfilled soil present on both sides, what kind of comments or guidelines could be provided?

Based on the analysis recommended by PEinc, during construction alternate backfilling and compaction of soil from one side of the foundation to the other. Too much backfill / compaction (force) on one side of the wall, without some offsetting compacted soil on the other side may cause failure. Just because construction takes place in a short time, compared to life of the structure, does not mean failure cannot happen during that short construction time.