Hi Focht3,
I have only looked at catalogs on-line from Humboldt and an actual hard copy ELE-Soiltest. Did a google search on soil testing equipment to get to the Humboldt catalog. Both of these list only small size shear boxes. I don't trust the results (45° to 52°) of testing well graded sand in a 2 inch shear box due to box interference. I am not familiar with Durham, I'll try a search for the web address. I prefer to do the tests in our lab (correctness freak) so if I don't find a vendor, I'll make one. I remember a number of years ago when landfill design and construction started up, there was some large size shear boxes being shown at conferences. Maybe I'll post the question elsewhere in the Eng-Tips forums. Thanks for your input.