Variation of the stress intensity factor along the crack front of interacting semi-elliptical surface cracks

In this study, the interaction between two semi-elliptical co-planar surfac e cracks is considered when Poisson's ratio v = 0.3. The problem is formula ted as a system of singular integral equations, based on the idea of the bo dy force method. In the numerical calculation, the unknown density of body force density is approximated by the product of a fundamental density funct ion and a polynomial. The results show that the present method yields smoot h variations of stress intensity factors along the crack front very accurat ely, for various geometrical conditions. When the size of crack 1 is larger than the size of crack 2, the maximum stress intensity factor appears at a certain point, beta (1) = 177 degrees, of crack 1. Along the outside of cr ack 1, that is at beta (1) = 0 similar to 90 degrees, the interaction can b e negligible even if the two cracks are very close. The interaction can be negligible when the two cracks are spaced in such a manner that their two c losest points are separated by a distance exceeding the small crack's major diameter. The variations of stress intensity factor of a semi-elliptical c rack are tabulated and charted.