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arXiv · 1810.00043

Flow-Arrest Transitions in Frictional Granular Matter

Ishan Srivastava·Leonardo E. Silbert·Gary S. Grest·Jeremy B. Lechman
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Abstract

The transition between shear-flowing and shear-arrested states of frictional granular matter is studied using constant-stress discrete element simulations. By subjecting a dilute system of frictional grains to a constant external shear stress and pressure, friction-dependent critical shear stress and density are clearly identified with both exhibiting a crossover between low and high friction. The critical shear stress bifurcates two nonequilibrium steady states: (i) steady state shear flow characterized by a constant deformation rate, and (ii) shear arrest characterized by temporally decaying creep to a statically stable state. The onset of arrest below critical shear stress occurs at a time $t_{c}$ that exhibits a heavy-tailed distribution, whose mean and variance diverge as a power law at the critical shear stress with a friction-dependent exponent that also exhibits a crossover between low and high friction. These observations indicate that granular arrest near critical shear stress is highly unpredictable and is strongly influenced by interparticle friction.

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Ishan Srivastava, Leonardo E. Silbert, Gary S. Grest, Jeremy B. Lechman. 2019-01-30. Flow-Arrest Transitions in Frictional Granular Matter. https://doi.org/10.1103/physrevlett.122.048003

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