Shear modulus discontinuity in fiber networks

Fibrous networks such as collagen are common in physiological systems. One important function of these networks is to provide mechanical stability for cells and tissues. It has been shown that athermal coarse-grained models of fibers with bending and stretching interactions can explain the experimental observations. By applying an extensional or shear deformation, subisostatic fiber networks with only central force interactions undergo a phase transition from a floppy to a rigid state. By simulating various network models, we confirm that although the network’s stiffness exhibits a discontinuity, the transition is critical in nature. We study the finite-size scaling behavior of this discontinuity in order to identify the corresponding non-mean-field critical exponent in the thermodynamic limit.