溪洛渡高拱坝蓄水期谷幅变形特性与影响因素分析  

Analysis on valley deformation of Xiluodu high arch dam during impoundment and its influencing factors

作　　者：梁国贺[1] 胡昱[1] 樊启祥[2] 李庆斌[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [2]中国长江三峡集团公司,湖北宜昌443002

出　　处：《水力发电学报》2016年第9期101-110,共10页Journal of Hydroelectric Engineering

基　　金：国家重点基础研究发展计划(973计划)(2013CB035902);国家自然科学基金(51279087;51339003);水沙科学与水利水电工程国家重点实验室科研课题(2015-C-02)

摘　　要：水库蓄水诱发的库岸变形现象对坝工结构的工作性态和工程整体的安全状态都有直接影响,及时掌握水库蓄水期间库岸岩体及坝工结构的真实变形状态,对于工程安全具有重要意义。针对我国溪洛渡高拱坝首次蓄水期间出现的显著的河谷谷幅收缩问题,收集整理了库区岩体及坝工结构的变形监测资料,通过统一坝体外观监测系统和内部垂线监测系统的基准点,获得了拱坝坝体及坝基岩体的真实变形状态,总结了坝体与库岸岩体变形的时空分布规律,认为坝体变形已受到坝址岩体变形的影响。在此基础上,本文通过建立逐步回归模型,分析了河谷谷幅发展过程与库水位、气温及其他作用因子的相关性,结果显示谷幅收缩过程主要由其他作用分量主导,而与库水位及气温的相关性较小。鉴于当前河谷谷幅收缩的趋势仍未完全收敛,对于谷幅收缩现象亟需进行机理研究以预测其未来发展趋势。Valley deformation of the reservoir behind a high arch dam at initial impoundment stage affects the current working behaviors of the dam and its long-term safety. Monitoring the deformation of reservoir valley and hydraulic structures is crucial to engineering security. This paper presents a case study of the Xiluodu super-high arch dam project, which is subjected to a significant decrease in valley width at initial impoundment stage. For this reservoir, we obtained the field data of dam deformation in its abutment region collected by the monitoring system of its structures and foundation, along with the field data of valley deformation and its temporal and spatial variations. A preliminary analysis indicated that the dam body has been squeezed by its abutments. A multiple regression model of valley deformation was developed using the least-square method, and it was used to analyze the effects of reservoir stage, atmospheric temperature and time effect on valley deformation. Results show that time effect has been the major factor causing a large proportion of the valley deformation, rather than reservoir stage or temperature. At present the ongoing valley deformation of this reservoir is not yet finished and therefore a further study for mechanism analysis of the valley deformation is suggested in this paper.

关 键 词：库岸变形 高拱坝 水库蓄水 谷幅收缩 

分 类 号：TV642.4[水利工程—水利水电工程]