Compaction Testing
Compaction Testing
(OP)
Hello,
Could someone give me some insite about different methods of determining field compaction of building/pipeline subgrades. I know of the nuclear desometer but have also heard that it is not very accurate with crushed rock. Is there anything out there that can quantitatively determine the compaction accurately?
Thanks
Could someone give me some insite about different methods of determining field compaction of building/pipeline subgrades. I know of the nuclear desometer but have also heard that it is not very accurate with crushed rock. Is there anything out there that can quantitatively determine the compaction accurately?
Thanks





RE: Compaction Testing
Nuclear Density Gage-Can present problems with crushed rock, calcareous materials, and in trenches
Drive Sleeve or Cylinder - Volumetrically accurate but not good for rock or soils containing rock fragments
Sand Cone - Accurate and typical calibration basis test for nuclear, but not accurate in porous materials and/or where vibration is present
Rubber Balloon - Not used much but would be the most accurate for your application
RE: Compaction Testing
RE: Compaction Testing
RE: Compaction Testing
I have found the nuke to be very accurate and reliable. It has undergone scrutiny by myself and probably over a hundred different contractors each of whom had their own incentives to see their numbers pass, and it has done the job.
I been testing bottom ash (USCS sand with some gravel) using the sand-cone method for about a year now, and I get extremely consistent results with that, too. An error of two pounds for me would mean a decreace in at least 3% compaction, which would make even a 97% be a potential failing test, and like I said, I don't often have problems.
All of these methods are both based on the consistency of your fill. If you are using manufactured fill like crushed rock, you can expect your tests to be reliable. If you have opted for native material to save on costs, you will basically be relying on the skill, experience, and knowlege of your technician. You will want a straight-arrow testing lab for those jobs to ensure a good result.