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Isostatic phase transition and instability in stiff granular materials

Cristian F. Moukarzel
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Abstract

In this letter, structural rigidity concepts are used to understand the origin of instabilities in granular aggregates. It is shown that: a) The contact network of a noncohesive granular aggregate becomes exactly isostatic in the limit of large stiffness-to-load ratio. b) Isostaticity is responsible for the anomalously large susceptibility to perturbation of these systems, and c) The load-stress response function of granular materials is critical (power-law distributed) in the isostatic limit. Thus there is a phase transition in the limit of intinitely large stiffness, and the resulting isostatic phase is characterized by huge instability to perturbation.

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BibTeXRIS

Cristian F. Moukarzel. 1998-07-09. Isostatic phase transition and instability in stiff granular materials. https://doi.org/10.1103/physrevlett.81.1634

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