The blast- induced crack initiation, propagation and arrest along both grooving and non- grooving directions in grooving directional fracture blasting are simulated by using the extended finite element method (XFEM) in the ABAQUS software. The results show that, it is 10 μs earlier in the grooving direction for the charge explosion to initiate cracks than in the non-grooving direction; while the crack propagation in the non-grooving direction does not see clear stages, the crack propagation in the grooving direction is clearly in three stages: the accelerating crack propagation, the unstable crack propagation and the decelerating crack propagation; the crack arrest time along the grooving direction is 60 μs more as compared with that in the non-grooving direction. During the crack propagation stage, the average speed of the unstable propagation in the grooving direction is 1343 m/s, while, it is 44% less in the non-grooving direction with the average speed of 600 m/s. This indicates that the groove is benecial for releasing the blast energy, and increasing the crack speed to a higher level. The groove has obviously the guidance effect in the extension direction of cracks, for the average crack length in the grooving and non-grooving directions is 124 mm and 45 mm, respectively. The XFEM method shows a promising prospect in simulating the crack propagation in the grooving directional blast.

extend finite element method (XFEM)  /  directional fracture blast  /  grooving borehole  /  blast induced cracks