Crack interaction, coalescence and mixed mode fracture mechanics

Multiple cracks are often observed in engineering structures; and their interaction and coalescence may significantly affect the lifetime of component or structure. In this paper, the general features associated with crack interaction and coalescence are presented, and the conditions for coalescence in various forms are reviewed. A model has been developed based on the principles of mixed mode fracture mechanics, to provide a rational explanation for the phenomenon of crack interaction and to predict the coalescence conditions. The latter is found to agree reasonably with the experimental observations.