Mechanism of dynamic and static combined load inducing rock burst in thin coal seam

stress condition and energy conversion of rock burst caused by dynamic and static combined load were theor The etically analyzed. Accordingly the mechanism of rock burst induced by dynamic and static combined load was proposed. In addition, the stress features around the workface under different coal seam thicknesses were numerically studied. Subsequently, the transmitting law of stress wave caused by stress releasing blasting was analyzed using micro-seismic monitoring system. The dynamic and static combined load characteristics of thin coal seam and the rock burst induced were studied. The results show that the stress concentration at thin coal seam is much higher than that at thick one, and the peak stress zone is much close to coal wall, and the stress gradient is larger. As the dynamic load caused by mining directly acts on the high stress zone, and the stress drop caused by mining, and the elastic energy releasing density in volume is higher than that of thick one, as a result of the combined effects of stress and energy, the rock burst risk liability of thin coal seam mining work face is higher than that of thick one, and the rock burst mechanism of thin coal seam obviously corresponds with that of dynamic and static combined load inducing. Based on the mechanism of rock burst caused by the interaction of dynamic and static load, the principles and technologies in controlling rock burst were developed for thin coal seam.