下伏采空区的煤矿地表地震动力响应模拟

Seismic dynamic response of ground surface above goaf of coal mine

针对中国煤矿多分布于7度及7度以上的地震烈度区,煤矿大规模开采,在矿区地层中留下了大面积、立体分布的空间,一些开采位于工业区或居住区的下部等问题,采用FLAC3D软件,建立了不同条件下的数值模型,对下伏采空区的煤矿地表地震响应进行分析.模拟结果显示:在剪切地震波的作用下,下伏采空区煤矿地表的最大水平加速度受到地下采空区的影响.讨论了在采深及采空区填充参数不同的情况下,地表监测位置的响应值变化.

Chinese coal mines are mostly located in the region with seismic intensity of 7 or higher. The vast tridimensional mined-out spaces formed in the strata of mine goaf have been increasing due to large-scale coal mining exploitation. Especially some underground mines are located in the industrial and residential areas. The study analyzed the seismic response at the ground surface transferred from the mine goal by using FLAC3D numerical models for various conditions. The results show that the peak values of the ground surface wave （PGA） for an earthquake SH wave are affected by existing underground spaces of the goal. These effects have been analyzed and evaluated at monitoring positions on the ground surface with different depth and filling conditions of the ~oaf.