锦屏一级水电站坝顶变形监测方法分析

Analysis of dam crest deformation monitoring method for JinpingⅠHydropower Station

为验证锦屏一级水电站大坝坝顶变形监测的可靠性,介绍了大地测量、GNSS(全球导航卫星系统)、垂线3种监测系统及大地测量系统与垂线系统坐标系之间的角度转换公式,通过角度转换将各坝段变形方向统一至径、切向,进而更好地对坝顶变形进行多手段的对比分析。结果表明:随库水位的升降变化,坝顶向下游或上游的变形明显,与库水位相关性较好,坝顶变形具有趋势性和周期性;此外,对比分析了3种监测系统间的误差及优劣,最终确定了较为可靠的坝顶变形监测手段。

In order to verify the real reliability of dam crest deformation of JinpingⅠHydropower Station,3 monitoring systems,such as geodesy,GNSS(Global Navigation Satellite System)and vertical line system,and the angle conversion formula between geodesy system and vertical line system are introduced.Through angle conversion,the deformation direction of each dam monolith was unified to radial and tangential direction for carrying out multi-means comparative analysis of dam crest deformation.The results showed that:with the rising or falling of reservoir water level,the deformation of dam crest towards downstream or upstream was obvious,which had a good correlation with reservoir water level;the trend and periodicity of dam crest deformation were demonstrated;besides,the errors,advantages and disadvantages of these 3 different monitoring systems were analyzed,and finally a more reliable dam crest deformation monitoring method was determined.