关键词: 大坝右岸, 覆盖层, 防渗墙, 渗流, 防渗排水措施

Abstract: The overburden of a dam is the deepest in China, whose maximum depth of the right bank is 420 m. There is a large amount of leakage on the right bank during operation. The underground water level of right bank is high and seepage failure has occurred at the local hillside and the drainage gallery. Combining site inspection and the existing monitoring records, seepage character analysis is conducted. The main source, seepage path, seepage stability and defect are analyzed. Aiming at the problems of the right bank, two kinds of seepage control system and new drainage gallery is planned. As well, FEM is used to calculate the effect on reducing leakage and the underground water level. The calculation results show that the bottom of the new cut-off wall and curtain grouting in the section 0+610~0+710 can effectively reduce the leakage and the local water head, and the additional drainage holes can lower the water head of gallery, which is beneficial to the right bank slope stability.

Key words: right bank of the dam, overburden, cutoff wall, seepage, anti-seepage and drainage measures