Viscous Effects on the Crack Propagation in Elastomers

In the experiments proposed in Corre et al. (2020) on the dynamics of fracture in elastomeric membranes, the speed at which crack propagates is directly correlated to the amount of pre-stretching applied to the membrane. Moreover, the numerical analysis in Kamasamudram et al. (2023) has shown that the evolution of crack is influenced by the viscosity of the material. In this paper, a mechanical model is proposed for the description of the initiation and propagation of cracks in elastomers according to the experimental evidence of Corre et al. (2020). A variational theory for finite visco-elasticity is formulated that incorporates phase-field fracture. The model accounts for a viscous macro-stress describing the rate-dependency of strains and a viscous micro-stress related to the rate-dependent micromechanical phenomena occurring in the fracture process. The model is implemented in a finite element code, and numerical simulations are performed that show the influence of viscosity on the crack propagation.