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arXiv · 1103.1767

Creep and fluidity of a real granular packing near jamming

Van Bau Nguyen·Thierry Darnige·Ary Bruand·Eric Clement
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Abstract

We study the internal dynamical processes taking place in a granular packing below yield stress. At all packing fractions and down to vanishingly low applied shear, a logarithmic creep is evidenced. The experiments are analyzed under the scope of a visco-elastic model introducing an internal "fluidity" variable. For all experiments, the creep dynamics can be rescaled onto a unique curve which displays jamming at the random-close-packing limit. At each packing fraction, a stress value is evidenced, corresponding to the onset of internal granular reorganisation leading to a slowing down the creep dynamics before the final yield.

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Van Bau Nguyen, Thierry Darnige, Ary Bruand, Eric Clement. 2011-06-27. Creep and fluidity of a real granular packing near jamming. https://arxiv.org/abs/1103.1767

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