Modeling the direct shear test of a coarse sand using the 3D Discrete Element Method with a rolling friction model

Abstract

In this research, a direct shear test was modeled using the 3D Discrete ElementMethod (DEM). The results are compared against experimental data. The realsand was modeled as about 70,000 spheres, with sizes consistent with the realgrain size distribution, using a rolling friction model to include the sand’s grainshape. It is shown that, the stress path can be appropriately reproduced, butthe dilatancy were very difficult to replicate.Finally, specimens with up-scaled material were tested. Although the unscaledmaterial was the most representative, the response of the particles that wereup-scaled twice was slightly less accurate, but with a considerable decrease ofcomputation time.