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Dilatancy and Friction in sheared granular media

F. Lacombe·S. Zapperi·H. J. Herrmann
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Abstract

We introduce a simple model to describe the frictional properties of granular media under shear. We model the friction force in term of the horizontal velocity v and the vertical position z of the slider, interpreting z as a constitutive variable characterizing the contact. Dilatancy is shown to play an essential role in the dynamic, inducing a stick-slip instability at low velocity. We compute the phase diagram, analyze numerically the model for a wide range of parameters and compare our results with experiments on dry and wet granular media, obtaining a good agreement. In particular, we reproduce the hysteretic velocity dependence of the frictional force.

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F. Lacombe, S. Zapperi, H. J. Herrmann. 1999-08-25. Dilatancy and Friction in sheared granular media. https://doi.org/10.1007/s101890050052

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