Stress and stress-structure controlled failure processes in deep-engineering rockmass

The development towards deeper underground is an inevitable trend in rock mechanics research and rock engineering construction. During deep underground construction, disasters such as extensive rock spalling, deep fracturing, large-volume collapse, large extensive deformation of hard rocks, and rockbursts of various types frequently occur. They are characteristic of high-stress-induced internal rock fracturing and disintegration of geological structures usually accompanied by energy release, which are completely different from the instability issues in shallow rock engineering. Therefore, a research approach for stress controlled and stress-structure controlled failure processes in deep engineering rockmasses has been proposed. Starting from recognition of geological characteristics of deep underground engineering and the characteristics of different types and levels of disasters, this paper elucidates the effects of stress and geological structure on the process of rockmass failure, and presents the ideas of developing laboratory and in-situ testing techniques, establishing predictive analysis theory and developing warning methods with some typical research achievements. The principles, methods, and technical measures for controlling the stress controlled and stress-structure controlled disasters mentioned above are proposed. Typical results and applications were used to illustrate the proposed research approach.