CYCLIC DIRECT SIMPLE SHEER TESTING OF A BEAUFORT SEA CLAY

Results are presented for undrained direct simple shear tests on a Bea ufort Sea cohesive soil. Monotonic and one-way cyclic loading response characteristics are identified for a number of loading scenarios. The critical level of repeated loadings (CLRL) is determined for two over consolidation ratios from tests having 30 000 cycles of loading. Postc yclic strength tests indicate that one-way cyclic loadings not causing failure have a strain-hardening effect on the material. High strain-r ate testing is found to increase soil strength by as much as 40% compa red with typical testing strain rates.