A contact model for the yielding of caked granular materials

TL;DR

This paper introduces a visco-elastic contact model for caked granular materials in DEM simulations, capturing multiple loading mechanisms and enabling analysis of elastic and failure properties.

Contribution

It presents a novel combined loading model for caked granular spheres, with validation against failure tests and insights into load mode relevance.

Findings

Model accurately predicts failure under various loadings

Failure criteria compare well with experimental data

Reveals importance of different load modes in failure

Abstract

We present a visco-elastic coupling model between caked spheres, suitable for DEM simulations, which incorporates the different loading mechanisms (tension, shear, bending, torsion) in a combined manner and allows for a derivation of elastic and failure properties on a common basis. In pull, shear, and torsion failure tests with agglomerates of up to 10000 particles, we compare the failure criterion to different approximative variants of it, with respect to accuracy and computational cost. The failure of the agglomerates, which behave according to elastic parameters derived from the contact elasticity, gives also insight into the relative relevance of the different load modes.