1991 Volume 53 Issue 4 Pages 21-30
The effect of loading speed on soil failure was studied by using a high speed triaxial compression test. Tests were conducted at 0.35-6.2m/s loading speed to compress soil specimens of silty loam and sandy loam at different moisture contents. The axial stress at fracture and the failure energy per unit volume increased with increase in loading speed up to certain critical speeds, however they decreased as the speed increased further. Two types of soil failure such as brittle failure and plastic flow were noticed which depended on the loading speed. Test soil specimens failed in brittle failure at lower loading speed. The mode of soil failure changed to platic flow at higher loading speed.
The volume of test soil specimen increased with increase in loading speed. In one case the test soil specimen dilated clear on shearing along a slip plane at lower loading speed. In the second case the barreling of cylindrical specimen consisted of the top and bottom conical shaped wedge or only one with small crack or fluidization of soil on all sides of test soil specimen at higher loading speed were observed.
