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arXiv · 2202.00041

Quantitative understanding of the onset of dense granular flows

Kasra Farain·Daniel Bonn
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Abstract

The question when and how dense granular materials start to flow under stress, despite many industrial and geophysical applications, remains largely unresolved. We develop and test a simple equation for the onset of quasi-static flows of granular materials which is based on the frictional aging of the granular packing. The result is a non-monotonic stress-strain relation which - akin to classical friction - is independent of the shear rate. This relation suffices to understand the below-threshold deformations of aging granular media, and its solid-to-liquid transition. Our results also elucidate the (flow) history dependence of the mechanical properties, and the sensitivity to initial preparation of granular media.

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Kasra Farain, Daniel Bonn. 2022-09-12. Quantitative understanding of the onset of dense granular flows. https://doi.org/10.1103/physrevlett.130.108201

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