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Footprints in Sand: The Response of a Granular Material to Local Perturbations

Junfei Geng·D. Howell·E. Longhi·R. P. Behringer·G. Reydellet·L. Vanel·E. Clement·S. Luding
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Abstract

We experimentally determine ensemble-averaged responses of granular packings to point forces, and we compare these results to recent models for force propagation in a granular material. We used 2D granular arrays consisting of photoelastic particles: either disks or pentagons, thus spanning the range from ordered to disordered packings. A key finding is that spatial ordering of the particles is a key factor in the force response. Ordered packings have a propagative component that does not occur in disordered packings.

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Junfei Geng, D. Howell, E. Longhi, R. P. Behringer, G. Reydellet, L. Vanel, E. Clement, S. Luding. 2003-04-03. Footprints in Sand: The Response of a Granular Material to Local Perturbations. https://doi.org/10.1103/physrevlett.87.035506

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