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arXiv · 1402.6473

Avalanche contribution to shear modulus of granular materials

Michio Otsuki·Hisao Hayakawa
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Abstract

Shear modulus of frictionless granular materials near the jamming transition under oscillatory shear is numerically investigated. It is found that the shear modulus $G$ satisfies a scaling law to interpolate between $G \sim (ϕ- ϕ_J)^{1/2}$ and $G \sim γ_0^{-1/2}(ϕ-ϕ_J)$ for a linear spring model of the elastic interaction between contacting grains, where $ϕ$, $ϕ_J$, and $γ_0$ are, respectively, the volume fraction of grains, the fraction at the jamming point, and the amplitude of the oscillatory shear. The linear relation between the shear modulus and $ϕ- ϕ_J$ can be understood by slip avalanches.

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Michio Otsuki, Hisao Hayakawa. 2014-10-06. Avalanche contribution to shear modulus of granular materials. https://doi.org/10.1103/physreve.90.042202

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