Do any of you own test equipment such as a DCP and use it to check compaction between engineer tests. Sometimes I would like to know how the compaction is going on noncritcal projects. I'm installing a retaining wall that requires 95% compaction for 8' behind the wall. I thought about using the DCP test to see how it is going. I will not be using a soil engineer on this project because it is on my property. Thanks, Tim
I use a probe or the stomp test, but I rarely have any trouble with compaction.
I use a probe similar to the ones soils engineers use. When I first started I would use it to see how the compaction felt right after the soils engineers tested it and gave their reading. By doing this a few times and with experience, you can become pretty accurate. The shape of the point on the probe can make a difference, so switching to a different probe can throw your "feel" off significantly.
Just remove a cone shape sample from the compacted area. Weight it. Boil it. Then weight it again.
what does boiling the dirt tell you?
I thought to find a proctor number they more or less bake it, to get rid of the moisture. (Besides, boiling takes all the flavor out of it....) :yup
http://www.concrete-catalog.com/soil_compaction.html this is a VERY good link to answer questions on soils compaction.
Correct me if i am wrong, but i always belived if soil was compacted to the 95% standard proctor density, that it would weight the same amount after you boiled it since all the mositure would be removed from it. EH? Matt
read that link i posted, it explains in great detail in laymen's terms as to how soil weights are determined, and how density tests are taken.
Bob I'm going to try your method. That may be accurate enough for the times I'm talking about. The price of a DCP is higher than I thought they would be. A probe is much cheaper and should work fine. That is a good website. It doesn't really cover the DCP test. I don't want to get into wieghing soil and baking. Thanks, Tim
I hope that method works for you. One time I was doing a compaction job and a soils engineer showed up with his probe. He was a huge guy - about 6'8" and weighed about 320lbs. I told him it wasn't fair because he big enough to push a probe through concrete. He just laughed. It turned out OK. Actually he was pretty accurate with his probe.
on a private/personal venue, i can see where any of these methods will work, even stamping your foot and seeing the impression it leaves also works. i've packed lots of soil in my life, but i'm no soils engineer. and if there is ANY chance of failure of a structure or parking lot due to my 2nd guessing my workmanship, i want somebody that is certified to sign off on what we've done. i guess what i'm saying, if a failure occurs and when the judge asks me what qualifications i have to determine the quality of the soil compaction i did, i'm able to tell him none.....the soils engineer took the tests and passed them.
That's called delegating responsibility. (It's also called CYA.) Whatever you call it, you sleep better at night.