Valley amplitude and chord deformation monitoring is an important means of dam safety monitoring. In view of the current situation of valley amplitude and chord monitoring, combined with the particularity of application scenarios with high altitude and large temperature difference, a full-automatic and all-weather valley amplitude and chord monitoring system is developed by integrating laser ranging and Internet of Things. It has been applied to the Longyangxia and Lijiaxia dams in the upper reaches of Yellow River. At the same time, the main influencing factors of laser ranging accuracy are analyzed based on the monitoring data, and the calculation method of laser distance influenced by air temperature and pressure is established. Through observation data and system stability calculation, the stability and adaptability of the system are verified.

high arch dam, valley amplitude deformation, automatic laser ranging

谷幅弦线变形监测是大坝安全监测的重要手段。针对谷幅弦线监测现状，结合高海拔、大温差应用场景下的特殊性，融合激光测距和物联网技术，研发了全自动全天候谷幅弦线监测系统，并在黄河上游龙羊峡和李家峡大坝进行了应用。同时，依据监测数据分析了激光测距精度的主要影响因素，建立了受气温和气压影响的激光距离计算方法。通过观测数据和系统稳定性计算，验证了该系统的稳定性和适应性。

高拱坝, 谷幅变形, 激光自动测距