Abstract:
Rock burst mitigation and monitoring is a challenge during deep coal mining. Theoretical analysis,numerical simulation,laboratory tests and field monitoring are all used for researching this issue. First,the occurrence mecha- nisms of three types of rock burst ( i. e.,strain rock burst,fault slip rock burst and hard roof rock burst) are re- searched. Second,two new burst liability indexes are proposed to improve the evaluation system of burst liability,which makes the burst liability evaluation system more suitable for deep coal mining. Third,the precursor information charac- teristics of the three rock burst types are given. Forth,the corresponding monitoring-warning and combined pressure re- lief methods are proposed. At last,synchronization technique of drilling and monitoring is developed. Main conclusions are as follows:① Deep strain rock burst is the result that the energy accumulation of surrounding rock system is larger than that of superposition of energy release and energy dissipation. Compared with shallow mining,the released energy of deep hard roof fracturing increases and deep fault slips more easily. ② When evaluating burst liability of deep strain rock burst and hard roof rock burst,burst energy speed indexes of unloading confining pressure and combined coal- rock need to be added except the national standard,respectively. For deep fault slip rock burst,the two new indexes are all need to be added. ③ Monitoring and warning of deep strain rock burst and deep hard rock burst should depend on energy and stress criteria,while for deep fault slip rock burst,energy criterion is the priority. ④ Priorities for miti- gating deep strain rock burst are protective seam mining,large-diameter drilling,floor fracturing and water infusion. Priorities for hard roof rock burst are protective seam mining,roof fracturing,large-diameter drilling,floor fracturing and water infusion. Priorities for fault slip rock burst are protective seam mining,large-diameter drilling and water infu- sion. ⑤ When using the synchronization technique of drilling and monitoring,drilling powder and stress change can be monitored for potential burst warning during drilling process. System establishment of control technique based on scien- tific classification still will be the direction of future research.