Application of borehole camera technology in the identification of an instantaneous strain-structural-plane slip rockburst

The prediction of instantaneous strain-structural-plane slip rockbursts in deep-buried hard rock tunnels is a complex problem needing to be solved. An engineering case with a burial depth of 2375 m was taken for in situ testing. The structural plane distribution in surrounding rock was visualized, and the dominant influence of structural planes in the formation of rockbursts was discussed. Results showed that when the sidewall of tunnel is parallel to the structural plane developed in the surrounding rock or intersects the structural plane at a small angle (less than 30°), the instantaneous strain-structural plane slip rockburst risk is higher and the dominant position of structural plane is obvious. The evolution of rock mass fractures in rockburst-affected zones is demonstrated by the expansion of primary fractures, and no new fractures are generated. Different distributions of structural plane in surrounding rock provide different energy accumulation environments for rockburst incubation. The results offer a reference to the rockburst estimation and prediction, which has important theoretical value and engineering significance.