摘要
新疆北疆碾压混凝土坝是国内外在极端恶劣条件下修建的第一座百米级全断面碾压混凝土重力坝,工程已正常运行12 a,监测数据表明:坝体上部混凝土温度已接近准稳定场,腹心混凝土温度降至稳定温度场还需10~15 a;高水位运行至今,坝基及坝体水平位移均向下游移动,对比同类型工程,本工程水平位移在正常范围内。通过建立回归模型,分析得出温度及水位是影响横缝开合度及坝体水平位移的主要因素,时效位移年变幅均逐年减小,且变化速率逐渐降低,呈收敛趋势。大坝总渗流量在水位基本保持一致时逐年降低、排水孔加密后扬压力降幅明显。越冬层层间温度、渗透压力均满足规范及设计要求,新旧混凝土结合完好,工程实施的温控措施合理有效,高水位运行后,大坝是安全的,成果对严寒寒冷地区的工程设计、建设及运行管理具有重要的指导及借鉴意义。
A RCC dam in North Xinjiang is the first 100 m grade full-section RCC dam built under extremely severe condition at home and abroad,which already operates for 12 years.The relevant monitoring data show that the temperature of the concrete on the upper part of the dam body already approaches to the quasi-stable temperature filed,while a period of 10~15 years is still necessary to be taken for the temperature dropping of the concrete inside the dam body to the stable temperature field.The horizontal displacements of both the dam foundation and the dam body move downstream since the operation of the dam under high water level.Compared with the similar project,the horizontal displacement of this project is still within a normal range.Through the analysis made by means of establishing the relevant regression model,it is obtained that both the temperature and the water level are the main factors to affect the opening degree of the transverse joint and the horizontal displacement of the dam body,while the yearly variation amplitudes of the timeliness displacements are all decreased year by year along with gradual decrease of the variation rate which exhibits a trend of convergence.The total seepage of the dam is decreased year by year when the water level basically maintains consistent,while the decreasing amplitude of the uplift is obvious after densifying the drain-holes.Both the interlayer temperature and seepage pressure of the overwintering layers meet the specifications and design requirements,while both the new and old concretes are better bonded.It is demonstrated that the temperature control measures applied to this project are reasonable and effective,thus the dam is safe during the operation under high water level.The study result has a certain referential significance for the design,construction and operation management of the similar project in cold region.
作者
吴艳
朱明远
周富强
美丽古丽
WU Yan;ZHU Mingyuan;ZHOU Fuqiang;Meiliguli(Xinjiang Institute of Water Resources and Hydropower Research,Urumqi 830049,Xinjiang,China)
出处
《水利水电技术》
北大核心
2019年第12期106-112,共7页
Water Resources and Hydropower Engineering
基金
国家重点研发计划(2016YB0201000)
国家自然科学基金项目(51479209)
