The influence of layer thickness on the stress intensity factor of a penny-shaped crack in a sandwiched viscoelastic bimaterial

Abstract

In this paper we consider a penny-shaped crack embedded in the central layer of a composite viscoelastic material. In order to study the possibility of fracture within the central layer, we study the response of the crack, namely the stress intensity factor (SIF), to a remote applied mode. Mode I deformation is considered and we investigate how the SIF varies with the thickness of the interior layer by modelling the crack with a continuous distribution function (representing special crack opening displacements) and hence reducing the problem to a singular integral equation. The integral equation becomes insufficient when the layer is infinitesimal; for this region a Wiener-Hopf technique is employed and a formula for the SIF is derived using matched asymptotic expansions. © 2004 Elsevier Ltd. All rights reserved.