Transient dynamic stress intensity factors around a crack in a nonhomogeneous interfacial layer between two dissimilar elastic half-planes

Dynamic stresses around a crack in a nonhomogeneous interfacial layer between two dissimilar elastic half-planes are obtained. The material constants vary continuously in the layer. An incoming shock stress wave impinges on the crack at right angles to the crack faces. In order to solve the problem, the interfacial layer is divided into several homogeneous layers that have different material properties. The boundary conditions are reduced to dual integral equations using the Fourier-Laplace transform technique. The equations are solved by expanding the differences of the crack faces in a series in the Laplace transform domain. The unknown coefficients in the series are determined using the Schmidt method. The stress intensity factors in the transform domain are inverted numerically in physical space. Using these numerical results, the stress intensity factors for a very thin layer can be estimated. (C) 2001 Elsevier Science Ltd. Ah rights reserved.