a boundary element analysis of crack-propagation mechanism of micro-cracks in rock-like specimens under a uniform normal tension

in this work, the mechanism for fracture of brittle substances such as rocks under a uniform normal tension is considered. the oriented straight micro-cracks are mostly created in all the polycrystalline materials resulting from the stress concentrations. the present work focuses on the interactions of the pre-existing micro-cracks, which can grow and propagate within a rock-like specimen. the micro-crack initiation and propagation in rock-like specimens is investigated using the fortran code tddcrack2d, which is a 2d displacement discontinuity method (ddm) for crack analysis, a boundary element computer code based on the linear elastic fracture mechanics (lefm) theory. in the present work, a higher order ddm is used to implement special crack tip elements for estimation of the stress intensity factors (sifs) and crack initiation angles for the wing-crack problems initiated at different angles from the original micro-crack tips in an infinite specimen under a uniform tension.