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The slip and instability mechanisms of coal‐rock parting‐coal structure (CRCS) under coupled dynamic and static loading were investigated using theoretical analysis and numerical simulations, and the fracture and instability processes were described by monitoring the displacement, strain, and acoustic emissions (AEs) of coal and rock parting blocks. Based on the parameters of dynamic load, three different effects on slip and instability characteristics of CRCS were presented, and the effect mechanisms of static stress, as well as amplitude and frequency of dynamic stress wave, were analyzed in detail. Finally, the direct effect on the slip and instability strength of CRCS and the frequency range of dynamic load for generating synchronous slip along two discontinuities sandwiched between coal and rock parting blocks were discussed. This work is relevant for early warning coal‐rock dynamic disasters that are triggered by the slip and fracture instability of CRCS under coupled dynamic and static loading in coal mines.

Coal burst has become one of the most serious hazards in longwall coal mines of many countries, and extensive studies have been conducted on the mechanism, prediction, and prevention of coal bursts. However, most of these studies focus on qualitative descriptions of burst environments and specific case analyses. Few studies have been carried out to explore knowledge through a number of past coal bursts in longwall mines. The main objective is to quantitatively analyze the current burst‐prone conditions in longwall coal mines of China and to summarize corresponding lessons. A database consisting of 54 major coal bursts was established. The characteristics and contributing factors of involved coal bursts were analyzed quantitatively, and high‐risk areas that are common in coal mines were then identified. Finally, some suggestions and lessons were proposed. This study may help for identifying controlling factors and high‐risk areas at a specific mine, and it might provide insights into the control of coal bursts in longwall coal mines.

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Stress concentration of coal and rock mass is the intrinsic cause of rock burst, the dynamic evolution law of coal seam stress and roof rock stress during the advancing process of mining face is obtained by using the coal seam stress monitoring system and the developed surrounding rock stress monitoring system, In this paper, the stress variation law of coal and rock mass during mining and the correlation between them are analyzed in detail. In order to reduce the danger of rock burst caused by stress concentration, hydraulic fracturing measures of roof strata were adopted in the field, and the stress changes of coal and rock mass before and after hydraulic fracturing were compared and analyzed. The results of the inspection show: The vertical stress gradient is linearly correlated with the trend of coal seam stress. The influence of mining on the stress of rock seam is earlier than that of coal seam, but the influence of mining disturbance on the stress of coal seam is higher than that of rock seam; The increase amplitude of vertical normal stress of roof strata under mining disturbance is obviously higher than that of two horizontal stresses; the stress value of coal and rock strata decreases after hydraulic fracturing, and the decrease amplitude of stress in coal seam is larger than that of rock strata after hydraulic fracturing. The peak stress of coal seam moves toward stopping line than that before hydraulic fracturing. Field application shows that the stress evolution information of coal seam can provide the corresponding basis for anti-scouring measures and ensure the safe and efficient production of working face.