Interaction effect of a main crack emanating from a semicircular notch and a microcrack

The study of morphology of fracture surfaces cannot only answer the whole of the problems arising from the damage of microcracking. This damage generates energy dissipation and a stress field redistribution which contributes to the dissipation of the energy stored in the structure, and favours the stable propagation of the main crack. In this work, the finite element method is used to analyze the interaction effect of a main crack emanating from semicircular notch and a microcrack in order to understand the different mechanisms induced by this interaction and in particular the effects of reduction and/or amplification of the stress field between the macro and the microcrack. Two cases were considered: transverse and longitudinal displacement of the microcrack compared to the main crack. This kind of approach makes it possible to predict the predominating fracture mode, either by coalescence, or by deflection in the direction of mode II.