Abstract：The phenomena caused by rock brittle fracture can be divided into two types. One is related to the changes in physical-mechanical parameters and structual characteristics, which can be described as the rock fracture, reducing of bearing capacity and modulus, increasing of permeability and deformation, and the mutation of wave velocity parameter and resistivity. The another type is related to the releasing of energy and change of physical parameters, which is reflected as the increasing of AE, electromagnetic emission and infrared radiation. Experiment and theoretical rest is shown that the stress ratio between crtical point of brttle failure and and peaking point has a value range 70% to 80%, which has a value of nearly to 75%. From this research, one can use the cpmprehensive information source to indentify the critical point of brittle fracture.
2013, Vol. 34 
