地下厂房洞室群渗流场及渗控措施效果数值分析

Numerical analysis on seepage field and anti-seepage effect for underground powerhouse cavern

采用三维渗流场有限元方法,模拟地下厂房洞室群稳定渗流场。建立三维渗流场有限元分析模型,精确模拟排水孔的位置。通过多工况的计算,详细分析地下厂房洞室群渗流特性以及其中帷幕及排水幕的渗流控制效果,同时探讨坝基及消力戽排水孔间距对渗流场的影响。计算结果表明:地下厂房洞室群天然水位较高,渗流控制措施对厂房洞室群渗流场可起到很好的控制作用,排水孔的排水减压作用明显,防渗帷幕能够有效降低扬压力以及水力坡降的分布,有利于围岩稳定。另外,坝基及消力戽排水孔间距对渗流场影响并不明显。

By using finite element method of 3D seepage field,the paper simulated the steady seepage field in chamber group of underground powerhouse. The seepage calculation model was established and the drainage holes position was accurately simulated. It analyzed the seepage field characteristics of the underground powerhouse cavers and the seepage control effect of curtain and drainage. In addition,the effect of the drain holes space for the dam foundation and stilling bucket on the seepage field were analyzed. The results show that seepage control measures can obtain good seepage control effect because of the natural high water level. The role of drainage and decreasing pressure of drainage holes is obvious. The curtain can effectively reduce uplift pressure and distribution of hydraulic gradient,which is conducive to the stability of surrounding rock. The effect of dam foundation and space of bucket drainage hole on seepage field is not obvious.