Effect of Cracks Shape on the Stress Intensity Factor for Cracks near a Bimaterial Interface
Jinchao YUE, Nao-Aki NODA and Katsuya ONO
Abstract:In this paper a rectangular crack vertical to a bimaterial interface under mixed model loading is considered. The solution utilizes the body force method and requires Green's functions for perfectly bonded semi-infinite bodies. The formulation leads to a system of hypersingular integral equations in which the unknowns are three types of crack opening displacements. In the numerical calculation, the unknown body force densities are approximated by using fundamental density functions and polynomials. The results show that the present method yields rapidly converging numerical results for various aspect ratios of a rectangular crack near a interface. Then, the effect of a free boundary on stress intensity factors of a rectangular crack subjected to tension is discussed by comparing the results of an elliptical crack with a same area. Moreover, distributions of stress intensity factors are indicated in tables and figures with varying the shape of crack, distance from the interface, and elastic constants. Meanwhile, the effect of crack shape on the stress intensity factors in term of root area is investigated. It is found that the stress intensity factors are mainly controlled by the root area parameter almost independent of the crack shape. At last, the stress intensity factors of a rectangular crack in a infinite body are calculated under tension and shear stress at infinity. Key Words:Elasticity, Stress intensity factor, Body force method, Rectangular crack, Singular integral equation, Numerical analysis, Fundamental density function