Layered rock crack propagation judgment method based on crack tip plastic zone radius

The invention provides a stratified rock crack propagation judgment method based on the radius of a crack tip plastic zone, and relates to the technical field of rock mechanics. The method comprises the following steps: respectively obtaining critical plastic zone radiuses rpc, m and rpc, b of a stratified rock matrix material and a stratified surface material on the basis of two groups of stratified rock fracture experimental data of which the stratified normal directions are 0 degree and 90 degrees; determining whether crack propagation occurs or not based on the following two formulas: # imgabs0 #: determining that crack propagation occurs if any one of the two formulas meets; therefore, according to the method, whether crack propagation occurs or not can be judged based on the minimum radius of the crack tip plastic zone and the radius of the plastic zone of the crack tip in the bedding plane direction, and the propagation direction of the crack is calculated, so that the crack development condition can b