Rate-dependent transition from continuum damage to discrete fracture for dynamic brittle failure

摘要

Based on a combined damage/plasticity model for geologic materials and the bifurcation analysis of material failure, an analytical framework is established to study the rate-dependent transition from continuum damage to discrete fracture in dynamic brittle failure. A continuum damage model with different evolution equations for the tensile and compressive regime is developed for brittle materials. A vectorized model solver can be designed for large-scale computer simulation. A continuum tangent stiffness tensor is formulated based on the damage model so that the bifurcation analysis can be performed to identify the initiation and orientation of material failure. Sample problems are considered to exhibit the features of the proposed approach.