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arXiv · 0907.0012

Non-affine response: jammed packings versus spring networks

Wouter G. Ellenbroek·Zorana Zeravcic·Wim van Saarloos·Martin van Hecke
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Abstract

We compare the elastic response of spring networks whose contact geometry is derived from real packings of frictionless discs, to networks obtained by randomly cutting bonds in a highly connected network derived from a well-compressed packing. We find that the shear response of packing-derived networks, and both the shear and compression response of randomly cut networks, are all similar: the elastic moduli vanish linearly near jamming, and distributions characterizing the local geometry of the response scale with distance to jamming. Compression of packing-derived networks is exceptional: the elastic modulus remains constant and the geometrical distributions do not exhibit simple scaling. We conclude that the compression response of jammed packings is anomalous, rather than the shear response.

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Wouter G. Ellenbroek, Zorana Zeravcic, Wim van Saarloos, Martin van Hecke. 2009-06-30. Non-affine response: jammed packings versus spring networks. https://doi.org/10.1209/0295-5075/87/34004

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