水泥土搅拌桩防渗墙对土坝防渗效果的模拟研究

通过对水泥土搅拌桩防渗墙防渗效果进行研究，为水泥土防渗墙设计提供进一步的优化指标。通过测压管观测数据反演得出大坝土体实际渗透系数，建立渗流有限元模型并利用实测资料验证，对水泥土搅拌桩防渗墙在土坝中的施工位置和深度进行不同情景模拟分析，结果表明：加入防渗墙后，渗流稳定性增加，防渗效果明显。防渗墙越靠近坝体上游，坝体的渗流稳定性越好；防渗墙贯入深度越深，坝体的渗流稳定性越好。防渗墙的位置布置在坝体中部靠近上游处较为合理，但考虑实际工程中施工要求，适当将防渗墙位置后移布置在大坝轴线处，对于渗流量影响较小。

Simulation Study on Effect of Impervious Wall of Cement-soil Mixing Pile in Seepage Prevention of Earth Dam

The anti-seepage effect of the cement-soil mixing pile impervious wall was studied, providing further optimization indicators for the design of impervious wall. The finite element model of the seepage flow was established and verified by the measured data. Different scenarios were simulated for the construction position and penetration depth of the cement-soil mixing pile impervious wall in the earth dam. The results shows that after the impervious wall is added, the seepage stability increases and the seepage control effect is obvious. The closer the cutoff wall is to the upstream of the dam body, the better the seepage stability of the dam body; the deeper the penetration depth of the cutoff wall, the better the seepage stability of the dam body. It is reasonable to place the cutoff wall in the middle of the dam body near the upstream, but considering the construction requirements in the actual project, the position of the cutoff wall should be properly moved back at the axis of the dam, which has little influence on the seepage flow.