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arXiv · 0810.4891

Why Do Granular Materials Stiffen with Shear Rate? A Test of Novel Stress-Based Statistics

Robert P. Behringer·Dapeng Bi·Bulbul Chakraborty·Silke Henkes·Robert R. Hartley
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Abstract

Recent experiments exhibit a rate-dependence for granular shear such that the stress grows linearly in the logarithm of the shear rate, \dotγ. Assuming a generalized activated process mechanism, we show that these observations are consistent with a recent proposal for a stress-based statistical ensemble. By contrast, predictions for rate-dependence using conventional energy-based statistical mechanics to describe activated processes, predicts a rate dependence that of (\ln (\dotγ))^{1/2}.

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Robert P. Behringer, Dapeng Bi, Bulbul Chakraborty, Silke Henkes, Robert R. Hartley. 2008-10-27. Why Do Granular Materials Stiffen with Shear Rate? A Test of Novel Stress-Based Statistics. https://doi.org/10.1103/physrevlett.101.268301

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