煤田采空区对地面地震动的影响

Impact of Coal Mine Goaf on Seismic Ground Motion

研究了煤田采空区对地面地震动的影响以及采空巷道的动应力分布。采空巷道用地表下圆孔来近似模拟,入射波场为造成较大震害的SH波。该问题采用镜像法求解,利用波函数展开和内域型Graf加法公式将解答归结为一组无穷代数方程组的求解,截断该无穷代数方程组可求得该问题的数值结果。最后,通过算例考虑了圆孔的动应力集中和地表动位移。结果表明,圆孔的动应力集中和地表的位移取决于入射波频率、角度和圆孔半径、埋深。该研究结果为煤田采空区的地震安全工作提供有益的参考。

The impact of coal mine goaf on seimaic surface ground motion and its dynamic stress distribtrtion around the tunnel was investigated. The goal was modeled as a circular hole embedded in a half space, and the incident waves as the SH wave. The solution of the scattering of SH wave was given by a circular hole embedded in a haft space with mirror method. The wave function expansion and Graf addition theorem yielded a set of infinite linear algebraic equations, which could be truncated to get the approximate solution .The numerical examples showed that the concentration of dynamic stress and ground motion depended on the incident frequency, angle, radius of the hole, and the embedded depth. The result of this is referable to seismic safety in coal mine goat.