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arXiv · 1312.4136

Percolating Plastic Failure as a Mechanism for Shear Softening in Amorphous Solids

Vijayakumar Chikkadi·Oleg Gendelman·Valery Ilyin·J Ashwin·Itamar Procaccia
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Abstract

``Shear softening" refers to the observed reduction in shear modulus when the stress on an amorphous solid is increased beyond the initial linear region. Careful numerical quasi-static simulations reveal an intimate relation between plastic failure and shear softening. The attaintment of the steady-state value of the shear modulus associated with plastic flow is identified with a percolation of the regions that underwent a plastic event. We present an elementary ``two-state" model that interpolates between failed and virgin regions and provides a simple and effective characterization of the shear softening.

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Vijayakumar Chikkadi, Oleg Gendelman, Valery Ilyin, J Ashwin, Itamar Procaccia. 2013-12-15. Percolating Plastic Failure as a Mechanism for Shear Softening in Amorphous Solids. https://arxiv.org/abs/1312.4136

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