Universal Anisotropy in Force Networks under Shear

TL;DR

This study investigates the universal scaling properties of force networks in sheared granular packings, revealing that shear induces anisotropic length scales without altering the fundamental scaling behavior.

Contribution

It demonstrates that shear stress creates anisotropic length scales in force networks without changing their universal scaling properties, independent of contact network details.

Findings

Shear induces anisotropic length scales in force networks.

Universal scaling properties remain unaffected by shear.

Anisotropy ratio is independent of contact network specifics.

Abstract

Scaling properties of patterns formed by large contact forces are studied as a function of the applied shear stress, in two-dimensional static packings generated from the force network ensemble. An anisotropic finite-size-scaling analysis shows that the applied shear does not affect the universal scaling properties of these patterns, but simply induces different length scales in the principal directions of the macroscopic stress tensor. The ratio of these length scales quantifies the anisotropy of the force networks, and is found not to depend on the details of the underlying contact network, in contrast with other properties such as the yield stress.