上游式尾矿坝的固结及静动力稳定分析

Consolidation and static-dynamical stability of upstream tailings dam

结合四方金矿尾矿库工程项目研究碎石桩加固初期坝地基对坝体稳定性的影响。首先,采用限动层加振冲碎石桩的方案对初期坝地基进行加固,并通过排水固结法计算了碎石桩在不同深度时,固结度随时间的变化规律,确定了最优的加固方案;其次,基于实际工程地质勘察和室内试验的研究成果,利用SEEP3D反演分析了其渗流结果;最后,采用基于有效应力法的EFES-3D计算程序对尾矿库初期坝地基在碎石桩加固前后进行了静动力计算和坝坡稳定性分析。可以看出,利用碎石桩加固初期坝可以使坝体沉降量增大,坝坡顺河向位移减小,并且降低了坝体液化的可能性,使坝体的抗滑稳定明显提高。

The influence of gravel pile foundation reinforcement for the initial tailing dam of goldmine of Sifang Company on the dam stability is investigated. First, the foundation of the initial tailings dam is strengthened by combining the stopper layer with the gravel pile reinforcing system. The variation of the degree of consolidation with time for the gravel pile at different depths is revealed using the drainage consolidation method. The optimal reinforcing scheme is proposed. Second, based on the actual and experimental data, the seepage behavior is analyzed inversely by means of SEEP3D. Furthermore, by using the effective stress method in the EFES-3D software, static and dynamic stability of the dam is calculated and the slope stability is analyzed. The results show that gravel pile foundation reinforcement may lead to increase of the settlement and decrease of the dam slope displacement. It provides a method for reducing the possibility of the dam liquefaction and improving the stability against sliding of tailings dam.