We study a granular layer sheared under constant volume which simulates the fast undrained deformation observed in seismogenic faults. We examine the effect of grain size polydispersity and grain breakage on the thickness of shear bands. By implementing the model using the finite element method we provide an explanation for the geological formation of double cataclastic shear bands.

https://www.sciencedirect.com/science/article/pii/S0022509620302106