Abstract:
Rock burst is one of the more serious dynamic disasters in coal mines. With the continuous increase of mining depth, rock burst disasters are becoming more and more serious. In view of the characteristics of major rock burst disasters, combined with the research status and engineering practice of rock burst in recent years, the concept of engineering defect body is proposed and classified from the perspective of controlling major rock burst disasters through artificial implementation of projects. The deformation and failure mechanical characteristics and energy release mode of high homogeneous and intact impact coal were analyzed. The stress-strain curves of intact coal, fractured coal and coal with engineering defects were compared and analyzed. The energy accumulation, dissipation and release mode of coal with different mechanical properties were analyzed. The mechanical properties of impact coal and coal with engineering defects were analyzed from the aspects of elastic energy index and impact energy index of coal. By establishing the calculation formula of impact tendency of coal with engineering defects, the mechanical mechanism of engineering defects changing the impact tendency of coal was found, and the mechanism of engineering defects preventing and controlling major rock burst was revealed. The research and practice show that the engineering defect body changeshe stress distribution characteristics of the stope and the evolution law of the impact energy in the coal body through the modification of the inherent impact tendency attribute of the coal body. The engineering defect can effectively dissipate the impact elastic energy in the coal body in the process of coal seam mining, and avoid destructive rock burst. Combined with the geological mining conditions of the specific working face, the space-time layout scheme of the engineering defect body is given, and the technical methods for the prevention and control of rock burst by the engineering defect body are expounded. The prevention and control effect is tested, and the safe mining of the impact coal seam is realized.