Moment tensor analysis of acoustic emission for cracking mechanisms in rock with a pre-cut circular hole under uniaxial compression

Acoustic Emission (AE) technique and moment tensor (MT) analysis were both applied to study the spatial-temporal evolution of micro-cracks of coarse-grained granite samples, containing a circular opening, which were subjected to uniaxial compression. The results show that AE locations are in agreement with the macroscopic fractures, observed on the surface of the granite specimens after the end of the experiments. Shear cracks are dominant as the ratio is more than 40% of the total number of events, tension cracks are fewer, since they accounted for more than 30% of the total events, and mixed-mode cracks represent a minimum proportion.