The interaction of two parallel non-coplanar identical surface cracks under tension and bending

In this paper, the interaction between two identical, non-coplanar, semi-el liptical surface cracks is investigated. The interacting cracks are assumed to be in an infinite plate subjected to remote tension or to pure bending loads. The stress intensity factors (SIFs) for these cracks are calculated using three-dimensional linear finite element analysis. A parametric study involving the relative horizontal and vertical separation distance between the two surface cracks is carried out for a specific crack shape and crack depth to plate thickness ratios of 0.3 and 0.2, respectively. An empirical formula is derived that relates the effects of the relative positions of th ese cracks to their SIFs. (C) 1999 Elsevier Science Ltd. All rights reserve d.