玉龙喀什枢纽超高面板堆石坝的渗控方案及渗流分析

Seepage control design and 3D seepage analysis of Yulongkashi concrete face rockfill dam

玉龙喀什水利枢纽混凝土面板堆石坝高度为230.5 m,为超高型的面板堆石坝,高度接近目前世界最高的同类坝型。本文依据高面板堆石坝渗流控制设计原则,对坝体进行了分区设计,提出了坝体混合料和全爆破料两种分区方案。使用三维有限元法,全面分析了坝体坝基的渗流场状况。结果表明:在正常运行条件下,上游水头由面板、趾板、高趾墩、坝基帷幕承担,渗控系统发挥了良好作用,面板及各填筑分区水力梯度均小于破坏水力梯度;全爆破料方案的坝体填筑料的最大水力梯度小于混合坝料方案,但是面板的防渗负荷相对较大;在面板发生整体渗漏的极端情况下,坝内浸润线和下游溢出高程升高的程度有限,但是极可能发生渗透破坏;坝基灌浆帷幕减少两岸渗漏的作用明显,河床和两坝肩渗漏量很小,绕坝渗流并不明显,受到右岸单薄山梁影响,右岸渗漏量略大于左岸。本文成果可供相似工程借鉴。

The dam of Yulongkashi Water Project is a super-high concrete face rockfill dam with a height of 230.5m.Its height is close to the world's tallest similar dam type.According to the design principle of seepage control,dam zoning is designed.Two dam zoning schemes are put forward,namely the mixed material and the whole blasting material.The seepage prevention treatment is carried out.The seepage field of dam and foundation is analyzed comprehensively with three-dimensional finite element method.The results show that,under normal operation conditions,the total head contour of seepage is dense at face plate,toe plate,and curtain,and the upstream head is undertaken by these parts.The hydraulic gradient of dam zones is smaller than the destructive hydraulic gradient,and the seepage control system plays a good role.The maximum hydraulic gradient of filling material of whole blasting material scheme is smaller than the mixed material scheme’s.But the former’s anti-seepage load of the face plate is relatively large.In extreme case of face plate leakage,the rise of the phreatic surface and the downstream overflow elevation is limited,but seepage damage is likely to occur.The grouting curtain reduces the seepage of both banks remarkably.The seepage of riverbed and abutments is small,and the seepage around the dam is not obvious.The seepage in the right bank is slightly larger than left bank’s due to the thin hill on the right bank.The research results of this paper are valuable references for similar projects.