A Rock Crack Shear Fracture Criterion and the Experimental Study

摘要

The different criteria applications for opening propagation and shearing propagation for rock cracks are discussed. Two types of compression-shear fracture experiments for rock crack are conducted. The phenomena for rock crack fracture: firstly opening propagation and secondly shearing propagation under compression-shear loading condition are realized. A shear fracture criterion is constructed based on Coulomb-Mohr strength criterion. The adoption of the characteristic scale r_0 for the rock grain size used in the criteria is discussed. Experimental results are in good agreements with the values predicted by the shear fracture criteria.