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arXiv · 1808.04756

Micromechanical theory of strain-stiffening of biopolymer networks

Robbie Rens·Carlos Villarroel·Gustavo Düring·Edan Lerner
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Abstract

Filamentous bio-materials such as fibrin or collagen networks exhibit an enormous stiffening of their elastic moduli upon large deformations. This pronounced nonlinear behavior stems from a significant separation between the stiffnesses scales associated with bending vs. stretching the material's constituent elements. Here we study a simple model of such materials - floppy networks of hinged rigid bars embedded in an elastic matrix - in which the effective ratio of bending to stretching stiffnesses vanishes identically. We introduce a theoretical framework and build upon it to construct a numerical method with which the model's micro- and macro-mechanics can be carefully studied. Our model, numerical method and theoretical framework allow us to robustly observe and fully understand the critical properties of the athermal strain-stiffening transition that underlies the nonlinear mechanical response of a broad class of biomaterials.

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Robbie Rens, Carlos Villarroel, Gustavo Düring, Edan Lerner. 2018-08-14. Micromechanical theory of strain-stiffening of biopolymer networks. https://doi.org/10.1103/physreve.98.062411

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