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arXiv · 1108.4354

Length-Controlled Elasticity in 3D Fiber Networks

C. P. Broedersz·M. Sheinman·F. C. MacKintosh
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Abstract

We present a model for disordered 3D fiber networks to study their linear and nonlinear elasticity over a wide range of network densities and fiber lengths. In contrast to previous 2D models, these 3D networks with binary cross-links are under-constrained with respect to fiber stretching elasticity, suggesting that bending may dominate their response. We find that such networks exhibit a fiber length-controlled bending regime and a crossover to a stretch-dominated regime for lengths beyond a characteristic scale that depends on the fiber's elastic properties. Finally, by extending the model to the nonlinear regime, we show that these networks become intrinsically nonlinear with a vanishing linear response regime in the limit of floppy or long filaments.

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C. P. Broedersz, M. Sheinman, F. C. MacKintosh. 2011-08-22. Length-Controlled Elasticity in 3D Fiber Networks. https://doi.org/10.1103/physrevlett.108.078102

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