A dynamic adaptive eigenfracture method for failure in brittle materials

We present a dynamic adaptive eigenfracture algorithm for the study of crack propagation in brittle materials. The original eigenfracture method is an variational approximation of the Griffith-type fracture with convergence as the element size vanishes. To improve its convergence rate, we extend the eigenfracture approach by using the effective energy release rate as the adaptive refinement criteria. Elements are subdivided based on nested refinement method with a pull-back operation. The dynamic adaptive eigenfracture method is validated by comparing to three-point bending tests of concrete and pure-tension tests of the material PMMA. The predicted crack angle in concrete and the simulation results of fracture propagation speed in PMMA show excellent agreement with experimental measurements. Even through a relatively coarse mesh employed in the simulations, the dynamic adaptive eigenfracture method can address the problem of mesh biased crack path.