Rock burst risk analysis and prevention measures of island working face mining in area of cutting-off

Abstract

Under the influence of unreasonable geological conditions, mining layout and excavation connection, island working face will be set up in the layout of working face, which seriously affects the safe mining of the mine. In order to solve the problem of rock burst risk in the island working face of the cutting-off area, taking the 3 upper 1105 island working face in Gaozhuang Coal Mine as an example, the research method combining theoretical analysis, numerical simulation, data statistics and analysis is adopted to analyze the overlying structure characteristics, stress distribution law in the cutting-off region and roadway surrounding rock stability during the mining of the island working face. The results show that the peak stress of the leading support reaches 54.1 MPa during the mining of the 3 upper 1105 working face of the cutting-off area, and the impact risk area is determined based on the stress state and deformation of the surrounding rock of the roadway, which is mainly distributed in the range of 0-30 m before and after the cutting-off of the 3 upper 1107 working face. For the cutting-off region, large-diameter drilling hole was used to relieve pressure, and through on-site monitoring and inspection, micro-seismic and drilling cuttings did not exceed the critical value of early warning, and the effect of pressure relief and crisis relief was good.

Keywords

• island working face
• cutting-off
• rock burst risk
• stress distribution
• large-diameter drilling hole