Study on risk analysis and prevention of rock burst in working face under the influence of continous sharp corner coal pillar

Taking 14320 working face of Dongtan Coal Mine as the engineering background, the impacting factors of rock burst were analyzed by numerical simulation, theoretical analysis and engineering practice including coal rock bursting tendency, geological structure, in-situ stress and hard roof. The stress evolution characteristics of the area affected by continuous sharp coal pillars was studied, the dangerous areas and degree of rock burst in the working face were divided by composite index method and multi-factor coupling evaluation method, and the corresponding prevention measures were provided. The results show that the stress concentration degree of the return airway affected by the continuous sharp coal pillars is large, and the continuous sharp coal pillars have a stress accumulation effect, which is a strong rock burst danger area; the transportation roadway is affected by three faults and mining disturbance, which is a medium rock burst danger area; the open-off cut roadway is affected by the mine boundary of 50.2 m coal pillar and is a weak rock burst danger area. In view of the above rock burst danger areas, the comprehensive measures such as coal seam water injection, large-diameter drilling and drilling cuttings methods were adopted, which proves to be effective.