Abstract: From the perspective of geological conditions, dam foundation uplift pressure, dam body temperature field and operation conditions, comprehensive analysis of the causes of abnormal horizontal displacement of an arch dam is carried out. It is concluded that the abnormal radial horizontal displacement is mainly caused by the unfavorable working conditions, including the water level surge in low temperature season as well as water level rise during sudden drop of temperature. Furthermore, the measured radial displacement does not exceed the designed calculation results, which may provide optimization recommendations for daily operations.

Key words: arch dam, radial displacement, monitoring data, analysis of abnormal data

摘要： 从地质条件、坝基扬压力、坝体温度场及运行工况等角度，对某混凝土拱坝水平位移异常原因进行综合分析，得出异常水平位移主要为不利工况（包括低温季节水位骤升、气温骤降+水位上升）导致的测值突变，实测径向位移未超过设计计算结果，为日常运行管理提供优化建议。

关键词: 拱坝, 径向位移, 监测数据, 异常分析