On the Mechanism of Rockburst Prevention by Coal Mass Vibration
煤体振动方法防治冲击地压的机理研究

The mechanism of a new method for the rockburst controlcoal mass vibration is studied. In the experimental aspect, the fractal geometry method is applied to quantify the crack distribution in the coal mass, and experimental results show that the fractal dimension of the coal mass increases after the coal mass vibration, which means the number of cracks in the coal mass increases, but after the vibration lasts for a certain time, the increase of the fractal dimension will stop. The mechanical property changes of the vibrated coal mass are determined, and it is found out that the compressive strength, the elastic modulus and the postpeak modulus of the coal mass intend to decrease after vibration. The longer the vibration time and the higher the original stress level are, the more obviously the vibration will affect the mechanical properties of the coal mass. In the theoretical aspect, the analysis for the rockburst around the working face and the roadway is applied to prove that the stability of the