Stresses around a moving Griffith crack at an interface between a nonhomogeneous bonding layer and two dissimilar orthotropic half-spaces

Abstract

In this study, stresses were estimated for a moving interface crack located on the lower interface between a nonhomogeneous elastic layer and a lower orthotropic elastic half-space while the upper interface between the layer and the upper orthotropic elastic half-space was not weakened by any cracks. It was assumed that the moving crack was open at one end and closed at the other and moved at a constant speed. The material properties of the bonding layer were assumed to vary continuously from the lower half-space to the upper half-space. A self-equilibrated system of pressure was applied to the crack surfaces. The mixed boundary value conditions with respect to the crack were reduced to dual integral equations. To solve the equations, the differences in the crack surface displacements were expanded to a series of functions that equal zero outside the crack. The unknown coefficients in the series were solved using the Schmidt method. The stress intensity factors were calculated numerically for the case in which the lower and upper half-spaces are made of unidirectional glass fiber-reinforced epoxy composites.