Abstract:
The crack initiation and crack damage strengths of rock are the important indexes to evaluate the high stress failure of hard rock. Based on the Hoek triaxial compression tests and acoustic emission tests, a brittle rock-like model material that can characterize the physical and mechanical behaviors of basalt block is used to carry out researches on the deformation and failure characteristics, acoustic emission characteristics, crack initiation and damage stress threshold levels, rock initiation and damage strength characteristics of the model materials. The evolution characteristics of hard and brittle fractures of the model materials are revealed. The crack initiation and crack damage stress thresholds of the model materials are given. The crack initiation and crack damage strength envelopes of the model materials are defined. The initiation and damage strength characteristics of similar materials of basalt brittle are investigated. The research results may provide certain technical support for the early warning and prediction of stress-induced failures such as wall caving, rock-burst or rupture during the excavation of underground cavities in basalt areas.