Compaction requirements for subgrade or fill below a pile supported slab?
Compaction requirements for subgrade or fill below a pile supported slab?
(OP)
Are there any compaction requirements for the subgrade or fill below a pile supported slab (i.e. no reliance on the soil)?
We usually still call for 95% percent compaction on the standard Proctor, but I often wonder if this requirement could be relaxed since we aren't relying on the soil to support any of the building weight. But maybe there are other reasons why such a high level of compaction would be desirable.
We usually still call for 95% percent compaction on the standard Proctor, but I often wonder if this requirement could be relaxed since we aren't relying on the soil to support any of the building weight. But maybe there are other reasons why such a high level of compaction would be desirable.





RE: Compaction requirements for subgrade or fill below a pile supported slab?
Kieran
RE: Compaction requirements for subgrade or fill below a pile supported slab?
I'm no expert, but I would compact to 95% before the piles are driven. You might have to add a little bit of soil after they're driven as the soil will tend to self compact due to the pile driving vibration.
RE: Compaction requirements for subgrade or fill below a pile supported slab?
Usually before the piles are driven.
Why is 95% compaction needed? Why not something less stringent like 90% or even less?
RE: Compaction requirements for subgrade or fill below a pile supported slab?
Dik
RE: Compaction requirements for subgrade or fill below a pile supported slab?
RE: Compaction requirements for subgrade or fill below a pile supported slab?
RE: Compaction requirements for subgrade or fill below a pile supported slab?
RE: Compaction requirements for subgrade or fill below a pile supported slab?
RE: Compaction requirements for subgrade or fill below a pile supported slab?
What kind of critters are we talking about here?
Oh, it's that easy to achieve 90%?
RE: Compaction requirements for subgrade or fill below a pile supported slab?
Interesting point.
RE: Compaction requirements for subgrade or fill below a pile supported slab?
RE: Compaction requirements for subgrade or fill below a pile supported slab?
Really? Perhaps my location is different, but a typical load of granular material used for structural backfill weights approximately 100 lbs./c.f. in loose condition in a truck or stockpile and has a modified proctor of approximately 145 lbs/c.f., or 69% of modified proctor.