Interaction between a Crack and an Isotropic Tri-Material Media in Anti-plane Elasticity

Solution of a crack interacting with a tri-material under a remote shear load for anti-plane elasticity problem is considered in this paper. The main purpose of this work is to study the interaction between a crack and a tri-material for anti-plane elasticity problem. This can be achieved by determination of the stress intensity factors that allow the characterization of this interaction from the point of view of linear elastic fracture mechanics. The proposed method is based on complex variable solution of a screw dislocation together with logarithmic singular integral equations. The singular integral equation is then solved numerically by modeling a crack in place of several segments. Some numerical results are performed to show the effects of material property combinations and geometric parameters on the normalized mode-III stress intensity factors. The results show that the stiffer materials may always give retardation effect on stress intensity factors when a crack approaching interfaces. On the other hand, the softer materials may always give enhancement effect on stress intensity factors.