Crack path field and strain injection techniques in dynamic fracture simulations

Abstract

Dynamic fracture phenomena are studied employing low cost computational tools based on Finite Elements with Embedded strong discontinuities (E-FEM). Fracture nucleation and propagation are accounted for through the injection of discontinuous strain and displacement modes inside the finite elements. The Crack Path Field technique is employed to compute the trace of the strong discontinuity during fracture propagation. Unstable crack propagation and crack branching are observed upon increasing loading rates. The variation in terms of crack pattern and energy dissipation is studied and a good correlation is found between the maximum experimental crack speed and maximum dissipation at the onset of branching. Comparable results are obtained against simulations employing supraelemental techniques, such as phase-field and gradient damage models, considering coarser discretizations which can differ by two orders of magnitude.