1998 Volume 47 Issue 10 Pages 1059-1064
In this paper, we investigate crack extension behaviors for a linear isotropic elastic body with two parallel interacting cracks at the neighborhood of the main crack tip. By using the E-integral which is path independent even for a path containing stationary crack tips, we compute the energy release rate for all the crack tips at the onset of crack kinking. As a result, assuming the isotropy of fracture toughness of the body and judging from the criterion based on the energy release rate, we find that there exist the relative positions of the interacting cracks which promote or interrupt the straight extension of the main crack and which make the main crack jump to an extension of an interacting crack.
