Compacting soil under slab

[1190R]

I had an irrigation pipe leak about 2 feet in from the edge of a six-inch slab

Got it repaired but wondering about the best technique for putting the soil back in a compacted fashion

I've got a jumping jack compactor

 

[BurtEggley]

probably crushed granite and use a 4x4 etc., packing it under the slab. Soil will just slump again with no proper side support. Or put something the termites won't eat like some bricks at the edge and fill it with closed cell expanding foam like is done to fill voids under the slab. Those are what I might consider. I've never had luck packing soil under something. If it is loose enough to pack, it slumps out too easily over time.

 

[NUTTSGT]

Compacting under the slab ? I've used a 2x4 or approximately size piece of lumber to reach under and compact... basically compacting horizontally rather than normal vertical.

 

[d300]

Capture the side of the slab with 'something' to stop anything else from coming out then I'd drill some 2"-3" holes through the slab and fill (pump if you can) with some lean grout into the void. Without support, even a reinforced slab will crack if overloaded.

 

[carlaisle]

3/4" black pipe with appropriate fittings to expand up to a 2" cap on the end. Insert loose fill, ram until solid, repeat. You need a soil that has a decent non-expansive clay content, the right moisture level, and appropriate side access for this to work. Form work and non shrinking grout would be far less effort.

 

[jkeyser14]

Don't put loose soil back in the hole, you'll never compact it under the overhang. Instead, fill it with flowable fill (lots of sand with some cement) or flowable grout (lots of cement with some sand).

Seriously, google it.