Stress Response in Confined Arrays of Frictional and Frictionless Particles

TL;DR

This study uses computer simulations to analyze how stress propagates in three-dimensional granular materials with frictional and frictionless particles, revealing different behaviors and responses depending on particle interactions and system size.

Contribution

It provides a comparative analysis of stress responses in frictional and frictionless granular arrays, highlighting the applicability of elasticity theory and the transition to anisotropic behavior in frictionless systems.

Findings

Frictional packings match classical elasticity predictions for large enough systems.

Frictionless packings show a transition to anisotropic stress response with increasing size.

Particle displacement fields differ significantly between frictional and frictionless systems.

Abstract

Stress transmission inside three dimensional granular packings is investigated using computer simulations. Localized force perturbation techniques are implemented for frictionless and frictional shallow, ordered, granular arrays confined by solid boundaries for a range of system sizes. Stress response profiles for frictional packings agree well with the predictions for the semi-infinite half plane of classical isotropic elasticity theory down to boxes of linear dimensions of approximately forty particle diameters and over several orders of magnitude in the applied force. The response profiles for frictionless packings exhibit a transitional regime to strongly anisotropic features with increasing box size. The differences between the nature of the stress response are shown to be characterized by very different particle displacement fields.