Stationary shear flows of dense granular materials : a tentative continuum modelling

TL;DR

This paper introduces a simple continuum model for dense granular shear flows, incorporating compressibility, dilatancy, and Coulomb friction, and shows it aligns with experimental and numerical results.

Contribution

It presents a novel continuum framework that captures key behaviors of dense granular shear flows, emphasizing the roles of rate-dependent and rate-independent stresses.

Findings

Velocity and compaction profiles match experimental data

Model effectively describes free-surface and confined shear flows

Highlights importance of rate-dependent impacts and long-lived contacts

Abstract

We propose a simple continuum model to interpret the shearing motion of dense, dry and cohesion-less granular media. Compressibility, dilatancy and Coulomb-like friction are the three basic ingredients. The granular stress is split into a rate-dependent part representing the rebound-less impacts between grains and a rate-independent part associated with long-lived contacts. Because we consider stationary flows only, the grain compaction and the grain velocity are the two main variables. The predicted velocity and compaction profiles are in apparent agreement with the experimental or numerical results concerning free-surface shear flows as well as confined shear flows