Abstract: Crest settlement reservation of concrete face slab rockfill dams would effect flood prevention safety and visual image.Some dam crest elevation was found lower than design in operation as there was no settlement reservation in design, while some recorded settlement in operation exceeded the designed value as the settlement reservation in design was too small. By statistics of dams, the recorded settlement value was more than 0.1% of damheight. For enough settlement reservation in operation and good visual image of arch at middle part, settlement reservation no less than 0.5% of damheight was recommended.

摘要： 混凝土面板堆石坝坝顶预留沉降超高, 关系到大坝运行期的防洪安全及视觉需要。有些坝设计时坝顶未预留沉降超高, 运行后发现坝顶实际高程低于设计高程; 有的坝坝顶预留沉降超高值较小, 运行后实测沉降值超过预留值; 多座坝的坝顶沉降实测值大于坝高的0.1%。为了保证大坝运行期沉降稳定后, 坝体仍有足够的安全超高, 并能满足坝顶中部起拱的美感要求, 建议坝顶预留沉降超高值不小于坝高的0.5%。