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Reorganization of a dense granular assembly: the `unjamming response function'

E. Kolb·J. Cviklinski·J. Lanuza·P. Claudin·E. Clement
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Abstract

We investigate the mechanical properties of a static dense granular assembly in response to a local forcing. To this end, a small cyclic displacement is applied on a grain in the bulk of a 2D disordered packing under gravity and the displacement fields are monitored. We evidence a dominant long range radial response in the upper half part above the sollicitation and after a large number of cycles the response is `quasi-reversible' with a remanent dissipation field exhibiting long range streams and vortex-like symmetry.

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E. Kolb, J. Cviklinski, J. Lanuza, P. Claudin, E. Clement. 2004-01-14. Reorganization of a dense granular assembly: the `unjamming response function'. https://doi.org/10.1103/physreve.69.031306

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