Failure mechanisms of saturated sand under different loading frequencies: Experimental observation and constitutive modelling

Abstract

In this paper, we report on cyclic hollow cylinder tests on Fujian sand and Nanjing sand subjected to different loading frequencies. Depending on the loading frequencies we observed two distinct failure modes, i.e. cyclic mobility and cyclic instability. We proceed to develop a plasticity model to capture the features of our observations. The model employed a new flow rule for the effect of loading frequency on shear dilation and contraction characteristics to better reflect the changes in excess pore water pressure, deformation and strength of the saturated sand under cyclic loading. The model was validated by comparing numerical simulations with experimental results.