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arXiv · 1010.4890

Softening induced instability of a stretched cohesive granular layer

Hector Alarcon·Osvanny Ramos·Loïc Vanel·Franck Vittoz·Francisco Melo·Jean-Christophe Géminard
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Abstract

We report on a cellular pattern which spontaneously forms at the surface of a thin layer of a cohesive granular material submitted to in-plane stretching. We present a simple model in which the mechanism responsible of the instability is the ``strain softening'' exhibited by humid granular materials above a typical strain. Our analysis indicates that such type of instability should be observed in any system presenting a negative stress sensitivity to strain perturbations.

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Hector Alarcon, Osvanny Ramos, Loïc Vanel, Franck Vittoz, Francisco Melo, Jean-Christophe Géminard. 2010-10-23. Softening induced instability of a stretched cohesive granular layer. https://doi.org/10.1103/physrevlett.105.208001

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