峡谷区深厚覆盖层上面板堆石坝结构安全研究  

Study on Structural Safety of Faced Rockfill Dam on Deep Overburden in Deep Valley

作　　者：何欣[1] 魏匡民[2] 屈洁[1] HE Xin;WEI Kuangmin;QU Jie(PowerChina Northwest Engineering Corporation Limited.Xi'an 710065,China;Nanjing Hydraulic Research Institute,Nanjing 210024,China)

机构地区：[1]中国电建集团西北勘测设计研究院有限公司,西安710065 [2]南京水利科学研究院,南京210024

出　　处：《西北水电》2024年第2期82-88,共7页Northwest Hydropower

基　　金：国家重点研发计划重点专项(2021YFC3090101);中央级公益性科研院所基本科研业务费专项资金项目(Y322003,Y320005).

摘　　要：趾板直接建在覆盖层上的面板堆石坝,通过防渗墙、连接板、混凝土面板以及接缝止水构成完整的防渗体系,由于覆盖层的大变形以及岸坡区以及河床覆盖层区较大的差异变形使得整体防渗体结构安全面临严峻考验。依托新疆某电站面板堆石坝工程,室内试验与现场旁压试验相结合确定合理的覆盖层和筑坝料力学参数,采用数值计算方法优化分析了连接板宽度、防渗墙施工次序、混凝土面板宽度、面板柔性缝设置方式等措施对改善防渗体系应力变形的效果。结果表明:合理的连接板长度与分缝型式可减小连接板应力和接缝变位;防渗墙后期施工能显著改善墙体应力,减小面板分缝宽度和设置柔性缝均能较好控制面板的应力性态;对于覆盖层上的新疆某电站面板堆石坝,防渗墙与连接板接缝以及陡峭左岸周边缝剪切变形是控制该工程运行安全的重要因素,研究结果可为同类型土石坝设计建设提供借鉴。Faced rockfill dam with toe plate directly built on the overburden has a complete anti-seepage system consisting of the cutoff wall,toe plate,concrete slab and joins system.Due to the large deformation of the overburden and the large difference deformation of the bank slope area and the river bed,the anti-seepage structure faces severe challenges.In this paper,based on a CFRD project in Xinjiang,the reasonable mechanical parameters of overburden and dam material are determined by combining the laboratory test and the field pressuremeter test.The effects of toe plate width,construction sequence of cutoff wall,width of concrete slab and flexible vertical joints on improving the stress and deformation of anti-seepage system are optimized by numerical calculation method.The research results show that reasonable toe plate length and joint type can reduce the structure stress and joint deformation;later construction of cutoff wall can significantly improve the wall stress;reducing the slab width and setting flexible joints can better control the stress state of the slab.For the CFRD project in Xinjiang,the shear deformation of the joint between the cutoff wall and the connecting plate and the peripheral joint at the steep left bank is an important factor which controls the operation safety of the project.The study can provide reference for the design and construction of similar CFRD projects.

关 键 词：覆盖层 面板堆石坝 有限元 峡谷区 变形控制 

分 类 号：TV641[水利工程—水利水电工程] TU45[建筑科学—岩土工程]