Dynamic Caustics Analysis of Oblique Crack Propagation under Blast Loading

摘要

To study the dynamic fracture mechanical behavior of rock under blast loading, the crack propagation experiment in material containing a prefabricated oblique flaw was carried out using a transmission caustics system. Varieties of crack propagation velocity, crack extensions acceleration, and the dynamic stress intensity factor at the wing crack tip of the oblique flaw were studied. The relationship of them was analyzed. Experimental results show that two wing cracks appear at both tips of the oblique flaw. The crack velocity and acceleration oscillate as the crack propagates. The changes of the dynamic stress intensity factor also oscillate during the whole propagation process. The values of the dynamic stress intensity factor KdⅠ at the tips of the oblique flaw are bigger than that of the dynamic stress intensity factor KdⅡ. The results of the present research can provide a theoretical basis for the study of practical blasting engineering.