The mining depth has reached 1000 meters in Qingtonggou Mercury-antimony Mine, with a large number of mined-out area. It has high mine pressure potential bumping in the ore-body roof. In the process of deep mining, it had happened surrounding splitting failure and roof caving phenomenon. It seriously affect the safety mining of the lower ore-body. Using numerical simulation, this study analyze the complicated mining conditions of the mine and present the schemes that is overhead mining sequence with the lower stage being ahead of the upper stage, beneath the level of +300m. According to the simulation results of calculation and analysis, it makes the filling area from the original "V" shaped into the inverted "V" shape and effectively reduce the disturbance of deep mining on the upper mined-out area. The disturbance height of mining reduce to the level of +280m and it effectively reduce stress focus of secondary stress. This scheme provides security to the filling of the upper mined-out area and reduce the threat of rock burst.
Qingtonggou Mercury-antimony Mine has been more than 50 years. Short-hole Shrinkage Method has been applied to Qingtonggou Mercury-antimony Mine. After completing of mining of the orebody above the level of +300m, the mine formed a number of mined-areas. The mined-areas have been threatening the stopping of the mining beneath the level of +300m. In recent years, filling the mined-areas and recovering residual ores are mainly works. Today, the demand for Mercury and Antimony has become urgent. In order to meet the needs of economic development, the exploration has been strengthened. It found resources about 200,000 tons within +300 m~+150 m. In order to utilize resources, the mine decide to study on mining technology of the orebody.
Its covered depth is 900 m~1100 m. They strike 150° and dip toward the south at angles of 40°~50°. The major axis pitching to northeast at an angle of 40°~45°. The orebody thickness is between 0.8 m and 6 m and average thickness is 3 m. The ore body and surrounding rock is silicified dolomite, sandy dolomite etc.