Drying out Building Pad
Drying out Building Pad
(OP)
We are testing the compaction for a building pad. Per the Proctor Test, the optimum moisture content is 8% but the pad right now is at 16%. The pad is about 18" thick. Is there a rule of thumb as to how long it might take to dry to the optimum moisture content?





RE: Drying out Building Pad
RE: Drying out Building Pad
Soil Classification: SM
Temperature: 90High/60Low
Pad Thickness: 18"
RE: Drying out Building Pad
RE: Drying out Building Pad
I'm curious....8% optimum seems awfully low for that type of material. Could you post the Proctor curve?
RE: Drying out Building Pad
RE: Drying out Building Pad
If outside, of course, good weather and more mixing will be needed.
And if you can't get good weather, look at cement stabilization there also.
Finally, if only for floor support, maybe the spec is too rigid.
RE: Drying out Building Pad
I'm not a fan of 3-point Proctors. Not sure why this was done, but it can be problematic.
Assuming an accurate Proctor, you will have to scarify the soil to get any drying. Further, compacting 18 inches of SM material with a unit weight of 130+ pcf is difficult, even at optimum moisture.
Check the organics. Check for calcium absorption. Add cement if both of those parameters check out.
RE: Drying out Building Pad
Don't get into cement stabilization without first learning how to do field control on the modified fill materials. I'm not saying it's hard, but the time to do compaction testing is reference by ASTM and if you don't understand these logistics you may end up with a poorly documented QC program.
f-d
¡papá gordo ain't no madre flaca!
RE: Drying out Building Pad
RE: Drying out Building Pad
otherwise, scarify and hope for dry weather to dry out the soil. It is too wet.
RE: Drying out Building Pad
I'm imagining an underlayer of soil that is less permeable than the SM material and nowhere for the SM to drain to. if that were the case, i would be suspicious about the validity of the 16% m.c. Going a step further in speculationland, it would be worth looking at the situation for slab vapor regardless of the vapor barrier.
What method(s) are you using for testing in-place compaction and moisture content?