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arXiv · 1511.06045

Sensitivity of Granular Force Chain Orientation to Disorder-induced Metastable Relaxation

N. Iikawa·M. M. Bandi·H. Katsuragi
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Abstract

A two-dimensional system of photoelastic disks subject to vertical tapping against gravity was experimentally monitored from ordered to disordered configurations by varying bidispersity. The packing fraction $ϕ$, coordination number $Z$, and an appropriately defined force chain orientational order parameter $S$, all exhibit similar sharp transition with small increase in disorder. A measurable change in $S$, but not $ϕ~\&~Z$, was detected under tapping. We find disorder-induced metastability does not show configurational relaxation, but can be detected via force chain reorientations.

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N. Iikawa, M. M. Bandi, H. Katsuragi. 2016-03-02. Sensitivity of Granular Force Chain Orientation to Disorder-induced Metastable Relaxation. https://doi.org/10.1103/physrevlett.116.128001

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