金堆城尾矿坝加高方案数值模拟及稳定性分析

Numerical simulation and slope stability analysis in Jingduicheng tailings dam to be designed to increase the dam height

金堆城尾矿坝为了进行加高设计而对尾矿库区进行了地质钻孔勘探。基于实际钻孔勘探成果,最佳反演分析了各分区—尾矿砂和初期坝堆石体模型的渗透系数、物理力学指标和加高方案下的浸润面分布。结合加高设计方案,采用基于有效应力法的EFES-3D计算程序对该尾矿坝加高后的应力应变场进行了数值模拟和坝坡稳定性分析,得出应力应变场分布图和边坡安全系数。可以看出,在上游法加高方案下,尾矿坝坝坡有涌起抬高现象,安全系数有所降低,不利于尾矿坝的稳定安全和运行管理。为此提出了在加高方案设计中加强排渗设施建议。

The engineering geological drilling exploration for the Jinduicheng tailings dam area is carried out to serve the heightening design of enlarging its volume. According to the permeability, physico-mechanical parameters of the two zones, the tailing sand and the rockfill of initial dam and the distribution of saturation surface under the heightening design plan are determined by the inverse analysis based on the drilling exploration result. Combined with the heightening design plan, the applied numerical method is the finite element method; and the software is EFES-3D based on the effective stress. It can numerical simulate both the stress-strain field and safety factor of the slope under the heightening design plan, and be concluded that the dam slope up rush and the safety factor of slope reducing under the upstream heightening design plan, which is not profitable for dam stability and management. Also the measures of drain pipes in the design of enlarging the volume are proposed.