Numerical simulation of shear band formation in a frictional-dilational material

The explicit, finite difference code FLAC is used to model shear band development in isotropic, elastic-plastic, Coulomb, non-associated, non-hardening materials. The code reproduces shear band inclinations which depend on both the angle of friction and the angle of dilation. Localization occurs at the yield point. Shear band width is sensitive to the size of the finite difference mesh but is controlled also by the magnitudes of the friction and dilation angles. The distribution of shear bands throughout the specimen is also influenced by the values of friction and, to a lesser extent, of dilation. There is no suggestion that numerical instability or numerical truncation errors are responsible for shear band nucleation.