AN ENERGY BASED FAILURE CRITERION FOR USE WITH PERIDYNAMIC STATES

Peridynamics is a continuum reformulation of the standard theory of solid mechanics. Unlike the partial differential equations of the standard theory, the basic equations of peridynamics are applicable even when cracks and other singularities appear in the deformation field. Interactions between continuum material points are termed bonds. In this paper, a method for implementing a rate-dependent plastic material model within a peridynamic numerical code is summarized and a novel failure criterion is then presented by analyzing the energy required to break all bonds across a plane of unit area (energy release rate); with this, one can determine the critical energy density required to irreversibly fail a single bond. By failing individual bonds, this allows cracks to initiate, coalesce, and propagate without a prescribed external crack law. This is demonstrated using experimentally collected fracture toughness measurements to evaluate the energy release rate. Simulations are compared to experimental results.