Dynamic stress intensity factors for multiple parallel cracks in an infinite domain under the passage of a normal incident impact or blast P-wave

Abstract

A numerical technique based upon the symmetric-Galerkin boundary element method (SGBEM) for 2-D elastodynamics in the Laplace-space frequency domain and the principle of superposition of loads was introduced in this work to provide new numerical results for the dynamic stress intensity factors (DSIFs) for multiple parallel cracks in an infinite domain under the passage of an incident impact or blast P-wave normal to the crack faces. Seven test examples were presented and, compared to some DSIF results available in the literature, our Laplace-SGBEM results are able to clearly show the impact of wave scattering on the DSIFs. The results also depict a behavior known as the damped-like oscillation of the DSIFs about their corresponding static value which is caused by the interaction between scattered waves and the crack surfaces. The new results are expected to serve as benchmarks for future techniques to measure their own performance.