大藤峡二期围堰结构和渗控安全性研究  

Study on Structure and Seepage Control Safety of Second-Phase Cofferdam in Datengxia Water Conservancy Project

作　　者：左永振[1] 陈良 徐晗[1] 李波[1] 陈劲松[1] ZUO Yongzhen;CHEN Liang;XU Han;LI Bo;CHEN Jinsong(Changjiang River Scientific Research Institute,Changjiang Water Resources Commission,Wuhan 430010,China;Guangxi Datengxia Gorge Water Conservancy Development Co.,Ltd.,Guiping 537200,China)

机构地区：[1]长江水利委员会长江科学院,湖北武汉430010 [2]广西大藤峡水利枢纽开发有限责任公司,广西桂平537200

出　　处：《人民珠江》2023年第7期27-35,共9页Pearl River

基　　金：国家自然科学基金-联合基金重点项目(U21A20158);国家自然科学基金面上项目(51979010)。

摘　　要：大藤峡水利枢纽工程二期土石围堰是最重要的临时建筑物之一,其设计与施工是大藤峡水利枢纽工程的重大关键技术之一,为保障二期深水围堰工程安全,针对二期深水围堰的结构和渗控安全性进行了专题科研论证。针对深水抛填形成围堰密度难以确定和设计提出的单防渗墙接土工膜的防渗体系,从离心模型试验确定水下抛填密度与休止角、围堰填料的力学特性、填料与塑性混凝土接触面剪切特性、塑性混凝土材料特性等方面开展了试验研究,并开展了应力变形有限元计算分析和围堰渗透稳定性分析,对围堰进行了安全性分析评价和断面优化设计。二期围堰历经2个汛期安全挡水运行,总渗流量较小,最大沉降和水平位移均较小,科研工作较好地支撑了设计需求。The second-phase earth-rock cofferdam in the Datengxia Water Conservancy Project is one of the most important temporary buildings,and its design and construction reflect major key technologies of the Datengxia Water Conservancy Project.In order to ensure the safety of the second-phase deepwater cofferdam project,a special scientific research demonstration was conducted on the structure and seepage control safety of the second-phase deepwater cofferdam.In view of the difficulty in determining the density of the cofferdam formed by deepwater dumping and the feasibility of the anti-seepage system with a single anti-seepage wall connected to the geomembrane,experimental research was carried out through the centrifugal model test,so as to determine the underwater dumping density and angle of repose,the mechanical characteristics of cofferdam filler,the shear characteristics of the interface between filler and plastic concrete,and the characteristics of plastic concrete materials.The finite element analysis of stress deformation and the seepage stability analysis of the cofferdam were carried out,and the safety analysis evaluation and the section optimization design of the cofferdam were performed.The second-phase cofferdam has undergone two flood seasons of safe water retention operation,with a small total seepage flow,slight maximum settlement,and low horizontal displacement.The scientific research work has well supported the design requirements.

关 键 词：二期土石围堰 水下抛填 塑性混凝土 变形计算 大藤峡 

分 类 号：TU411[建筑科学—岩土工程]