Discontinuous rigidity transition associated with shear jamming in granular simulations

TL;DR

This paper studies the nature of the rigidity transition during shear jamming in granular materials, revealing it is discontinuous in the quasi-static limit for both frictionless and frictional particles, unifying jamming transition characteristics.

Contribution

It demonstrates that the shear jamming transition is discontinuous in the quasi-static limit, extending previous isotropic jamming results to shear-driven systems.

Findings

Discontinuous transition in frictionless disks at quasistatic shear.

Transition appears continuous at finite shear rates for frictional disks.

Transition becomes sharper as shear rate decreases.

Abstract

We investigate the rigidity transition associated with shear jamming in frictionless, as well as frictional, disk packings in the quasi-static regime and at low shear rates. For frictionless disks, the transition is under quasistatic shear is discontinuous, with an instantaneous emergence of a system spanning rigid cluster at the jamming transition. For frictional systems, the transition appears continuous for finite shear rates, but becomes sharper for lower shear rates. In the quasi-static limit, it is discontinuous as in the frictionless case. Thus, our results show that the rigidity transition associated with shear jamming is discontinuous, as demonstrated in a past for isotropic jamming of frictionless particles, and therefore a unifying feature of the jamming transition in general.