Numerical evaluation of three non‐coaxial kinematic models using the distinct element method for elliptical granular materials

Abstract

SummaryThis paper presents a numerical evaluation of three non‐coaxial kinematic models by performing Distinct Element Method (DEM) simple shear tests on specimens composed of elliptical particles with different aspect ratios of 1.4 and 1.7. The models evaluated are the double‐shearing model, the double‐sliding free‐rotating model and the double slip and rotation rate model (DSR2 model). Two modes of monotonic and cyclic simple shear tests were simulated to evaluate the role played by the inherent anisotropy of the specimens. The main findings are supported by all the DEM simple shear tests, irrespective of particle shape, specimen density or shear mode. The evaluation demonstrates that the assumption in the double‐shearing model is inconsistent with the DEM results and that the energy dissipation requirements in the double‐sliding free‐rotating model appear to be too restrictive to describe the kinematic flow of elliptical particle systems. In contrast, the predictions made by the DSR2 model agree reasonably well with the DEM data, which demonstrates that the DSR2 model can effectively predict the non‐coaxial kinematic behavior of elliptical particle systems. Copyright © 2016 John Wiley & Sons, Ltd.