塑性混凝土防渗墙在三峡二期围堰中的应用

三峡二期围堰防渗墙最大高度 74m ,其中墙深大于 40 m ,采用塑性混凝土。防渗墙经 1 998年夏季长江 8次洪峰 (三峡坝址最大流量 6 1 0 0 0 m3/s)考验 ,堰体渗透比降最大值 0 .1 0 8,小于堰基粉细砂设计允许值 0 .2 5 ;渗水总量约 5 0 L /s,小于设计估算基坑渗水总量 6 0 0 L /s,防渗效果显著

The Application of the Plastic Concrete Cut-off Wall in Second Stage Cofferdam of Three Gorges Project

The second stage cofferdam cut off wall of Three Gorges Project has a maximum height of 74m, among which walls greater than 40m depth were constructed with plastic concrete. These cut off wall underwent eight trials of flood peak of Changjiang River in summer, 1989(The maximum flow there was 61000m 3/s).The maximum percolation gradient of cofferdams is 0 108, which is less than the minimum allowable value 0 25 of silt fine sand on base of cofferdams. The total seepage discharge is about 50L/s, which is less than the design estimated seepage discharge of foundation 600L/s. The results of seepage prevention performance is very notable.