Abstract: In the flood season of 2005, because of upstream flood, the water level of Longyangxia reservoir went to the height of 2 597.62 m, approaching normal high water level for the first time since operation. By analysis on observation data of dam and damfoundation displacement, this paper explained the phenomenon of unclosed water level component of the radial displacement of arch crown, summarized the rules of damdisplacement and got to the conclusion that the damwas normal in operation.

摘要： 2005 年汛期, 黄河上游来水较好, 龙羊峡水库水位持续上升, 最高水位达2 597.62 m, 大坝自运行以来首次经受接近正常高水位的考验。对高水位运行期大坝及基础变位观测资料进行分析, 合理解释了拱冠径向位移水压分量不闭合现象, 总结出大坝的变位规律, 认为大坝工作状态正常。