Stress distribution law of steeply inclined horizontal sectional caving coal mining and prevention and control of rock burst

Abstract

In order to reveal the distribution characteristics of the stress field and rock burst mechanism induced in the horizontal segmented working face of steeply inclined coal seams, taking eastern No.1 mining area of Wangjiashan Coal Mine as an engineering background, the characteristics of rock burst behavior in the horizontal segmented working face were theoretically analyzed, and the evolution law of the stress field during the horizontal segmented mining process of steeply inclined coal seams was analyzed by numerical simulation; the mechanism of micro-seismicity inducing rock burst of roadway coal floor during horizontal sublevel mining in steeply inclined coal seams is revealed. The research results show that the rock burst risk of roof roadway is significantly higher than that of floor roadway. With the increase of working face segmentation, the vertical stress significantly increases, and the vertical stress concentration degree of roof roadway is higher than that of floor roadway. The maximum principal stress changes from the original horizontal distribution to the distribution along the vertical coal seam direction. After mining, the horizontal stress field of the coal at the working face tends to increase first and then decrease, and the horizontal stress on the roof side is significantly higher than that on the floor side. The peak value of the horizontal stress is linearly related to the mining depth. The prevention and control methods for rock burst in horizontal sublevel mining are proposed. The prevention effect is remarkable.

Keywords

• rock burst
• horizontal layered roof caving mining
• steeply inclined coal seam
• stress distribution characteristic
• numerical simulation
• drilling pressure relief