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arXiv · 1203.5996

Mechanical response of an inclined frictional granular layer approaching unjamming

A. P. F. Atman·P. Claudin·G. Combe·R. Mari
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Abstract

We present an orthotropic elastic analysis of frictional granular layers under gravity by studying their stress response to a localized overload at the layer surface for several substrate tilt angles. The distance to the unjamming transition is controlled by the tilt angle α with respect to the critical angle α_c. We find that the shear modulus of the system decreases with α, but reaches a finite value as αtends to α_c. We also analyze the vibration modes of the system and show that the soft modes play an increasing, though not crucial, role approaching the transition.

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A. P. F. Atman, P. Claudin, G. Combe, R. Mari. 2013-01-22. Mechanical response of an inclined frictional granular layer approaching unjamming. https://doi.org/10.1209/0295-5075%2F101%2F44006

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