Abstract: In the anti-seepage system of concrete face slab rockfill dam, the surface water stop for slab joint is an important part of the whole water stop system for concrete slab. At present, anchored water stop structure is used as most of surface water stops for joints of concrete face slab dams. There are some disadvantages of this structure, such as the gap between cover plate and slab, the difficulty of lapping between surrounding joints and vertical joints, the falling off of bolts due to ice pulling in water level change area and the corrosion of steel strips. Comparison between the coated water stop structure and the anchored water stop structure is carried out. To repair the surface water stop damage in water level change area of Nazixia hydropower station in severe cold area, the coated water stop structure is adopted. After three-year operation, it is proved that the coated water stop structure can effectively prevent the surface water stop from damage caused by ice pulling or expansion, greatly improve the reliability of slab joint seals, and is easy to maintain, which is worthy popularizing and applying.

Key words: slab joint, coated water stop structure, severe cold area

摘要： 混凝土面板堆石坝的面板防渗体系中，面板接缝表层止水是整个混凝土面板止水体系中的重要部分。目前面板坝接缝表层止水大多数采用锚固型止水结构，该结构存在盖板周边与面板之间有空隙、周边缝与垂直缝之间异型搭接困难、螺栓在水位变化区易发生冰冻拉拔脱落、钢板压条易锈蚀等缺点。本研究对面板接缝涂覆型止水结构与锚固型止水结构进行了比较，针对地处严寒地区的纳子峡水电站水位变化区表层止水出现的破损情况，采用涂覆型止水结构进行了修复。三年的运行考验证明，涂覆型止水结构可以有效防止冰拔或冰冻胀挤压引起的表层止水破坏，大大提高了面板接缝止水的可靠性，且便于维修，值得推广应用。

关键词: 面板接缝, 涂覆型止水结构, 严寒地区