The macro fracture failure of rock is a progressive process including formation, propagation, evolution and damage of its micro-crack, and also is a process in which energy dissipation and energy release are occurred. So, it is important to study and analyze the way and the rules when rock crack extending. And then it is significant for in-depth understanding of the nature about the rock damage. The abrupt structural failure criterion of rock is established from the viewpoint of energy based on the least energy consumption principle, and it's c...
