The research on Rockburst Risk of Working Face in Mining Caused by Water-Rich Area

Aiming at the phenomenon that many dynamics occur frequently in working face or roadway when the first mining face of mine A, 2-2upper201 is driven to the edge of water-rich area, the effects on original rock stress by draining water-rich area and rockburst risks in two different conditions of drainage and no-drainage are studied through some methods such as theoretical analysis and numerical analysis, based on working face 2-2upper201A(the second working face of Mine A). The findings are as follows: ①The drainage in water-rich area can damage aquifer, resulting in stress decrease inside damaged area and stress concentration in the edge; ②Considering the effect by draining water-rich area, rockbust scope and degree in damaged area will change. In detail, the range below water-rich with risk will shrink and degree of risk will decline, while the edge and outside of water-rich area will enlarge as risk rises. The field monitoring indicates that in the process of mining, stress increments on measure spots rank as the order of from large to small as follows: edge > outside > inside. When working face is driven to the edge of water-rich area, many drastic dynamics like coal blasting, wall carving will occur on the wall, which suggests that draining water-rich area has a great impact on rockburst risk of working face. The research result has very important guiding significance to rockburst prevention in water-rich area.