Unjamming of Granular Packings due to Local Perturbations: Stability and Decay of Displacements

Abstract

We study the mechanical response generated by local deformations in jammed packings of rigid disks. Based on discrete element simulations we determine the critical force of the local perturbation that is needed to break the mechanical equilibrium and examine the generated displacement field. Displacements decay as a power law of the distance from the perturbation point. The decay exponent and the critical force exhibit nontrivial dependence on the friction: Both quantities are nonmonotonic and have a sharp maximum at the friction coefficient 0.1. We find that the mechanical response properties are closely related to the problem of force-indeterminacy where similar nonmonotonic behavior was observed previously. We establish direct connection between the critical force and the ensemble of static force networks.

4 pages, 4 figures

References in corpus (3)

• The Jamming Transition in Granular Systems
• Sheared force-networks: anisotropies, yielding and geometry
• Elasticity from the Force Network Ensemble in Granular Media

Cited by in corpus (5)

• Unjamming due to local perturbations in granular packings with and without gravity
• Gravity Governs Shear Localization in Confined Dense Granular Flows
• Evolution of shear zones in granular packings under pressure
• Striped Patterns in Radially Driven Suspensions with Open Boundaries
• Convective Flows in Sheared Packings of Spherical Particles