深厚覆盖层上高土石坝坝基廊道安全性研究  

Safety of Gallery in High Rockfill Dam on Thick Overburden Layer

作　　者：冯蕊[1,2] 何蕴龙 曹学兴[3] 郭丽娜[4] 李玉起[2] Feng Rui;He Yunlong;Cao Xuexing;Guo Lina;Li Yuqi(State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China;Pearl River Hydraulic Research Institute,Guangzhou 510611,China;Huaneng Lancang River Hydropower Co.,Ltd.,Kunming 650214,China;Yunnan Technology and Business University,Kunming 651701,China)

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072 [2]珠江水利科学研究院,广州510611 [3]华能澜沧江水电有限公司,昆明650214 [4]云南工商学院,昆明651701

出　　处：《天津大学学报（自然科学与工程技术版）》2023年第5期513-523,共11页Journal of Tianjin University：Science and Technology

基　　金：国家重点研发计划资助项目(2018YFC0407105).

摘　　要：工程实践表明,建造在深厚覆盖层地基上的高堆石坝坝基廊道漏水问题仍然十分严峻,此类廊道连接坝基防渗墙和坝体心墙,结构和受力情况复杂,影响因素较多,是整个防渗系统的薄弱部位,研究廊道的破坏模式和规律,完善其结构设计理论,是当前亟待解决的重要课题.本文结合已建工程的实际情况,分析了坝基廊道运行过程中存在的具体问题,并建立了考虑廊道周围结构网格的精细化模拟、混凝土徐变、廊道与周围土体接触等多种影响因素的廊道计算模型,通过计算得到的廊道应力分布规律与廊道中实测钢筋应力分布规律一致,数值也比较相近,证明该方法能够合理反映廊道应力变形特性.分析表明:廊道拉应力主要出现在两岸基岩和覆盖层交界位置附近,及廊道内部顶拱和底板部位;廊道结构缝破坏形式与结构缝位置密切相关;当覆盖层河谷两岸坡度存在非对称性时,廊道在基岩和覆盖层交界位置会产生不同形式的裂缝,在陡坡侧容易出现环向裂缝,在缓坡侧容易出现剪切性质的斜裂缝,且缓坡侧的横河向拉应力、底板的顺河向拉应力值和范围均比陡坡侧大.Some foundation galleries in high rockfill dams built on deep overburden layers revealed that dam foundation gallery leakage is still a major problem.The gallery is a complex structure that connects the cutoff wall in deep overburden layers to the core wall in the dam body,and many factors affect its mechanical characteristics.Therefore,analyzing the failure mode,the main factors influencing the stress-strain behaviors,the influencing laws of the gallery and improving the design theory are important tasks.Based on the actual situation of the construction projects,the safety problems existing in the operation of the dam foundation gallery were analyzed.At the same time,to obtain a more reliable stress and deformation law for the gallery,this study establishes a gallery finite element calculation model that takes multiple influencing factors into account,such as the detailed simulation meshing,the creep of the concrete,and the contact between the gallery and surrounding soils.The calculated stress distribution of the gallery is consistent with the stress distribution reflected by the monitoring data.This proves that the approach can reasonably reflect the stress and deformation features of the gallery.The results showed that the tensile stress of the gallery concentrated near the junction of bedrock and overburden on both sides of the river,as well as at the top arch and bottom floor of the gallery.The failure of structural joints in the gallery was primarily caused by excessive opening deformation or dislocation,which was closely related to the position of the structural joints.The topographic conditions of the valley impacted the different crack forms near the two banks.Circumferential cracks were prone to appear on the side of the steep slope when the slope of the two sides of the overburden valley was quite different.On the side of the gentle slope,inclined shear cracks were common.And on the side of the gentle slope,the transverse tensile stress near the junction of bedrock,the tensile stress value and range o

关 键 词：廊道 高堆石坝 廊道结构缝 裂缝 深厚覆盖层 

分 类 号：TV641.4[水利工程—水利水电工程]