深厚覆盖层高坝坝基防渗系统地震反应规律研究  

Seismic response of dam foundation seepage control system of a high dam on thick overburden layer

作　　者：冯蕊 何蕴龙[2] FENG Rui;HE Yunlong(The Pearl River Hydraulic Research Institute,Guangzhou 510611,China;State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,China)

机构地区：[1]珠江水利科学研究院水利工程研究所,广东广州510611 [2]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《人民长江》2023年第7期121-127,共7页Yangtze River

摘　　要：对于修建在高地震烈度区深厚覆盖层上的高堆石坝,其由混凝土防渗墙和廊道组成的坝基防渗系统的结构特性和受力特性均比较复杂,对其抗震特性的探讨具有很大意义。以大渡河支流上的金平沥青混凝土心墙堆石坝为工程背景,采用三维非线性有限元模型和子模型技术,对防渗墙和廊道结构进行了地震时程分析。分析结果表明:廊道基岩搭接段和覆盖层交界处既是廊道静力工况时的拉应力极值区,也是廊道地震过程中动应力反应最强烈的部位;防渗墙动应力反应最强烈的区域为墙体上部岸坡基岩折坡点附近;考虑静、动荷载共同作用后,防渗墙和廊道应力变形规律相对静力工况变化较小。综合来看,在设计地震作用下,廊道和防渗墙的应力变形所受影响较小,坝基防渗系统的抗震性能较好。For high rockfill dams on thick overburden layers in high seismic intensity area,the structural and mechanical characteristics of dam foundation seepage control system composed of the concrete cutoff wall and gallery,are complex and always subjected to complicated loads.Therefore,the discussion on their anti-seismic characteristics is of great significance.In this paper,Jinping asphalt core rockfill dam built on a tributary of Dadu River was taken as a case.The seismic time history analysis for the cutoff wall and gallery was carried out by using three-dimensional nonlinear finite element model and sub model technology.The results show that under the static condition,the extreme tensile stresses exist near the junction of bedrock and overburden layers,where the strongest dynamic response of gallery also happens.In the cutoff wall,the upper part near the turning part of the right bank slope shows the strongest dynamic response.After superposing the static response with dynamic response,the deformation and stress distribution rules change slightly compared with those in the static state.On the whole,earthquakes have little effects on the stress and deformation of concrete cutoff wall and gallery,and the anti-seismic performance of the dam foundation seepage control system is good.

关 键 词：动力分析 防渗墙 廊道 堆石坝 深厚覆盖层 

分 类 号：TV641.4[水利工程—水利水电工程]