Modeling dry granular mass flows as elasto-visco-hypoplastic continua with microstructural effects. II. Numerical simulations of benchmark flow problems

Abstract

This paper continues Part I, in which dry granular mass flows were modeled as elasto-visco-hypoplastic continua with microstructural effects. A complete set of thermodynamically consistent constitutive equations was obtained, in which hypoplasticity was in particular incorporated to account for the frictional and plastic characteristics of granular media. Here the established thermodynamically consistent constitutive model is applied to investigate steady, isothermal shearing flows with incompressible grains of benchmark problems, namely, simple plane shear flow, inclined gravity-driven surface flow and plane Poiseuille flow. Numerical results show that the hypoplastic effect plays a significant role in the behavior of a flowing dry granular mass. The obtained profiles of the velocity and the volume fraction with hypoplastic features are obviously sharper and the shear-thinning effect is more significant than without such plastic effects. The present model shows a good potential to describe the complex elasto-visco-plastic behavior and the microstructural effects of granular flows simultaneously; wide applicability of the model in the fields of granular avalanches, debris and soil flows may be possible.