compacting wet clay during the rainy season.
compacting wet clay during the rainy season.
(OP)
What is the best way to compact wet clay to 95% mod that is being dumped on a site that has the water table just a few feet below the surface. Not to mention that this is the wettest time of year in louisiana. I'm building a house pad and the homeowner needs to pour the slab in the beginning of january. The lot is flat with pipelines running along the only two sides with a ditch and the the pipeline company won't let me cut ditches across there pipeline to help with drainage. I'm trying to not use lime because I don't have a stabilizer. I'm looking for tricks of the trade that I may not know about. I have a dozer ,excavator,tractor with discs and dump trucks. I'm trying to purchase a padfoot compactor.





RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
Dry it by using a disk harrow or cultivator and then compact it when it is about 1% over optimum moisture, using sheepsfoot compactor.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
I think I'm going to cut some 2' deep trenches every 20' in and around the pad site so that when I start tracking on the material the ground water will be able to flow into the trenches and not pump up into the fill that i'm going compacting. Then I'm going to stock pile the fill material in-between the trenches and disc it to dry it. as the fill material dries out I will cut the top dry layer off and use it in 6" lifts to get my compaction. Hopefully as I'm compacting it the ground water will go into the trenches and not up into my fill. Then I will have to muck out the trenches and backfill and compact them last. If anybody has a better idea that 's affordable, I'm open. As with all clients they can't see why there pad is going to cost more and take longer than there friends pad that was built in july. They also have a inlaw that is a very good carpenter that is telling them how easy it is to build a pad and he doesn't see what the problem is.
I'm sure everybody on this forum has dealt with the brother inlaw, uncle, coworker ect, ect,ect that knows more than the people that have been doing this for years.
The Smart thing to do would be wait until the conditions are better. But I'm going to try to get this pad to pass compaction for a reasonable price. They just don't know how hard it's going to be.
Thanks for all the replies it always helps to here other peoples opinions.
RE: compacting wet clay during the rainy season.
It is difficult to suggest something meaningful without knowing site conditions such as soil property and water table. Looks like you have a work plan, good luck, make sure you have enough pumps/sumps to perform continuous pumping.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
Old cement also works great.
Next, why 95 percent and percent of what? That 95 is practically impossible to get in clay and is not needed.
I'd see if I could convince inspector that if the unconfined compressive strength (by pocket penetrometer) is over 1.5 T/sf, you ought to then have a reasonably suitable pad made of clay. Tell 'em that is the bearing capacity (a pretty close to true statement).
RE: compacting wet clay during the rainy season.
Is there some granular fill between the clay and the ground floor slab? If so approximately how thick?
I think that the best that can be achieved is to get a clay pad that looks sound (old rejected cement if available as suggested by oldestguy would help), place a geotextile, then put a layer of granular material, proof roll and remove and replace soft spots, then test the granular fill layer. As oldestguy mentions 95% mod proctor not required. Perhaps a plate bearing test.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
As compared to wet clay, the sand ought to be a much better material, even if some different effort is needed.
The main risk is what you are aware of with bone dry sand running sideways. It also may migrate some laterally while compacting. However, since it is nearly a single sized material, it won't densify much with compaction, yet is relatively incompressible then. This means not much compactive effort is needed and less in the way of sand moving problems.
We used some Mississippi dredged sand material here (Wisconsin) and, when confined with enough width of fill, works well. You would not want to place the slab with its edge at or near the top edge of the fill.
Can't you form up the concrete slab edges to keep things in position at least while the concrete is setting up?
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.
RE: compacting wet clay during the rainy season.