Slope Failure Reanalysis of a Dilatant Dense Sand from CPTU and Laboratory Tests

Abstract

Geotechnical properties of dense to very dense sands at Channel Island Harbor in Oxnard, California, are re-evaluated after slope failures to select appropriate strength parameters for remedial and extension works. The revetment is excavated at a slope of 2:1 (horizontal: vertical) in estuarine and dune sands and covered with a geotextile filter and armor rock. Reanalysis of the slope stability explores laboratory and in situ strength conditions of peak, constant volume and residual angles for the sands. A stress-dilatancy theory provides the framework used in re-characterization of the soil and observed slope failure mechanisms. Effective friction angles are recommended for further slope stability analysis at that location.