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arXiv · 2112.00784

Micromechanical origin of plasticity and hysteresis in nest-like packings

Yashraj Bhosale·Nicholas Weiner·Alex Butler·Seung Hyun Kim·Mattia Gazzola·Hunter King
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Abstract

Disordered packings of unbonded, semiflexible fibers represent a class of materials spanning contexts and scales. From twig-based bird nests to unwoven textiles, bulk mechanics of disparate systems emerge from the bending of constituent slender elements about impermanent contacts. In experimental and computational packings of wooden sticks, we identify prominent features of their response to cyclic oedometric compression: non-linear stiffness, transient plasticity, and eventually repeatable velocity-independent hysteresis. We trace these features to their micromechanic origins, identified in characteristic appearance, disappearance, and displacement of internal contacts.

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Yashraj Bhosale, Nicholas Weiner, Alex Butler, Seung Hyun Kim, Mattia Gazzola, Hunter King. 2021-12-01. Micromechanical origin of plasticity and hysteresis in nest-like packings. https://doi.org/10.1103/physrevlett.128.198003

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