tamper near residential foundation wall

[helliot]

Hello all,

Background info: Retaining wall to be installed near a recently installed residential foundation. Being installed after the fact due to site grading changes. It is a cantilever style retaining wall, 4 feet exposed, and the base will be quite close to the foundation wall (4" away in places). Since the backfill around the residence was removed to cast the foundation, I had suggested they use a small motorized tamper to compact the soil under the base of the retaining wall in lifts as they backfill against the foundation wall - to obtain an adequate bearing capacity of soil for under the retaining wall base.

The cribber is concerned that this tamping may damage the foundation wall he has just completed. Does anyone have experience with damages created by compacting soil directly next to a residential foundation? I would imagine the worst-case would be bowing of the foundation wall or movement of the footing. I can't imagine a small tamper causing such damage, but I have never built a retaining wall so close to an existing foundation. Thoughts?

Thanks for reading,

- h.e.

 

[Ron]

If it is a small sled compactor and the concrete has already cured for a reasonable period of time, not likely to damage it.