Transient analysis of a mode-III crack propagating in a piezoelectric medium

The transient response of a semi-infinite, propagating crack subjected to dynamic anti-plane concentrated loading in a piezoelectric medium is investigated. A new fundamental solution for the piezoelectric material is proposed and the transient response of the propagating crack is determined by superposition of the fundamental solution in the Laplace transform domain. Exact analytical transient solutions for the dynamic stress intensity factor, the dynamic electric displacement intensity factor, and the dynamic energy release rate are obtained by using the Cagniard method of Laplace inversion and are expressed in explicit forms. The results indicate that the dynamic intensities of a propagating crack can be represented by the product of a universal function and the corresponding solution for a stationary crack. It is also found that the dynamic stress intensity factor and the dynamic energy release rate go to zero as the propagating speed approaches the Bleustein-Gulyaev piezoelectric surface wave speed under this particular boundary condition. (C) 2004 Elsevier Ltd. All rights reserved.