摘要
当前300 m级高拱坝的抗震性能评估已经普遍采用基于坝体-地基动力相互作用的分析模型,然而,包含地基的分析模型底部地震动输入边界的水平空间尺度可以达到几千米,空间跨度大,显然不应忽略地震动在模型水平外边界上的不均匀性,尤其是在近断层地震动作用下。为研究模型外边界均匀地震动输入对拱坝动力响应的影响,以某270 m高度的高拱坝为例,采用ETA(Event Tree Analysis)方法对比分析了均匀输入和考虑行波效应的非均匀输入对拱坝位移、应力和损伤响应的影响。研究发现,相对于均匀输入得到的拱坝应力响应结果,考虑行波效应的拱坝应力响应部分区域的最大拱向应力增大,而最大梁向应力减小,且地震动输入侧的应力增大明显;相对于均匀输入,考虑行波输入的坝体损伤响应规律主要是对坝面上的损伤有所减小,而对拱端处及坝底的损伤有所增大;从坝顶相对坝底的最大位移可以看出,行波输入相对于均匀输入的坝顶位移增大明显,且从空间上来看,在靠近左岸的坝体坝顶位移向上游增大明显,坝顶位移随着向右岸移动而不断减小,靠近右岸的坝体坝顶位移向下游增大明显。
The seismic performance assessment of a 300-m-level high arch dam has generally adopted an analysis model based on the dynamic interaction between the dam body and the foundation.However,the horizontal spatial scale of the ground motion input boundary at the bottom of the analysis model including the foundation can reach several kilometers,with a large spatial span.The non-uniformity of ground motion on the horizontal external boundary of the model should not be ignored,especially under near-fault ground motion.To study the influence of the uniform ground motion input of the external boundary on the dynamic response of the arch dam,this paper takes a certain 270-m-level high arch dam as an example and adopts the ETA method to analyze the influence of the uniform input and the non-uniform input considering the traveling wave effect on the displacement,stress,and damage response of arch dam.It is found that,compared with the stress response results of the arch dam obtained by uniform input,the maximum arch stress in some areas of the arch dam stress response considering the traveling wave effect increases,while the maximum beam stress decreases,and the stress on the input side of the ground motion increases significantly.Compared with the uniform input,the damage response law of the dam with traveling wave effect is mainly that the damage to the dam face is reduced,while the damage to the arch end and the dam bottom increases.From the maximum displacement of the dam top relative to the dam bottom,it can be seen that the traveling wave input increases the dam top displacement significantly relative to the uniform input.From the spatial point of view,the dam top displacement near the left bank increases significantly upstream,the dam top displacement decreases as it moves to the right bank,and the dam top displacement near the right bank increases significantly downstream.
作者
李静
朱明响
邢建营
陈健云
LI Jing;ZHU Mingxiang;XING Jianying;CHEN Jianyun(School of Infrastructure Engineering,Dalian University of Technology,Dalian 116023,China;China Water Resources Beifang Investigation,Design and Research Co.,Ltd.,Tianjin 300222,China;Yellow River Engineering Consulting Co.,Ltd.,Zhengzhou 450003,China)
出处
《人民珠江》
2025年第7期115-121,共7页
Pearl River
基金
国家自然科学基金资助项目(52079025)
国家自然科学基金重大研究计划(52192672)。
关键词
混凝土拱坝
行波效应
非均匀输入
有限元模拟
concrete arch dam
traveling wave effect
non-uniform input
finite element simulation
