空腹结构对重力坝静动力响应影响研究  

Study on influence from hollow structure on static and dynamic responses of gravity dam

作　　者：张军 何卫平 蒋忠宪 刘昊 ZHANG Jun;HE Weiping;JIANG Zhongxian;LIU Hao(Electric Power Research Institute of State Grid Hunan Electric Power Company Limited, Changsha 410007, Hunan, China;College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, Hubei, China;Hydropower Branch of State Grid Hunan Electric Power Company Limited, Changsha 410000, Hunan, China)

机构地区：[1]国网湖南省电力有限公司电力科学研究院,湖南长沙410007 [2]三峡大学水利与环境学院,湖北宜昌443002 [3]国网湖南省电力有限公司水电分公司,湖南长沙410000

出　　处：《水利水电技术》2020年第11期93-101,共9页Water Resources and Hydropower Engineering

基　　金：国家自然科学基金(51809152);国网湖南省电力有限公司科技项目(5216A518000N)。

摘　　要：针对空腹重力坝抗震问题,研究空腹结构对重力坝静动力响应的影响。首先分析了空腹结构对重力坝静荷载和动力特性的影响,并将前腿和后腿视为梁结构分析空腹重力坝的静态和动态受力特征。然后以凤滩空腹重力坝13#溢流坝段为基础,采用线弹性有限单元法对空腹坝静动力响应进行分析,并将空腹填充混凝土的实体坝作为对比方案。结果显示:静荷载作用时,空腹坝前腿梁主要为弯曲变形,后腿梁主要为两端受压变形;动荷载作用时,空腹坝前腿梁和后腿梁均为两端受拉(或受压)和弯曲的综合作用。空腹坝的静拉应力主要出现在坝踵和空腹顶部上游侧,动拉应力主要出现在坝踵、坝趾和空腹附近坝体,静动综合影响下坝踵和空腹顶部上游侧为抗震薄弱部位。受空腹结构影响,坝踵静动综合拉应力比实体坝高24%,坝趾静动综合压应力比实体坝高22%。Targeting at the earthquake resistance of hollow gravity dam,the influence from the hollow structure on the static and dynamic responses of the gravity dam is studied herein.The influence from the hollow structure on the static load and dynamic characteristics of the gravity dam is analyzed at first,and then both the static and dynamic mechanical characteristics of the hollow gravity dam are analyzed by taking its front leg and hind leg as beam structures.Afterwards,the static and dynamic responses of the hollow gravity dam are analyzed with the relevant linear-elastic finite element method by taking the No.13 overflow dam section of the hollow gravity dam of Fengtan Hydropower Station as the research basis,while the solid dam with the inner cavity filled by concrete is taking as a scheme for comparison as well.The result shows that so far as the hollow gravity dam is concerned,the front leg-beam mainly exhibits bending deformation and the hind leg-beam main presents compression deformations at both the ends under the effect of static load,while both the front leg-beam and the hind leg-beam are affected by the comprehensive effect consisted of tension(or compression)at both the ends and bending under dynamic load.The static tensile stress of the hollow gravity dam mainly occurs at the dam heel and the upstream side of the top of the inner cavity and the dynamic tensile stress mainly occurs at the dam heel,dam toe and the dam body near the inner cavity,while the dam heel and the upstream side of the top of the inner cavity are the aseismic weak locations under the static and dynamic comprehensive effect.Under the influence of the hollow structure,the static and dynamic comprehensive tensile stress at the dam heel is 24%higher than that of the solid dam,while the static and dynamic comprehensive compression stress at the dam toe is 22%higher than that of the solid dam as well.

关 键 词：结构动力学 空腹重力坝 地震响应 前腿梁 后腿梁 

分 类 号：TV312[水利工程—水工结构工程]