摘要
综合考虑岛礁与海水的动力耦合作用、固、液介质截断边界处的波动辐射效应和地震波动输入问题,建立二维局部成层的岛礁-海水系统地震反应分析模型,通过与陆域水平成层场地和斜坡平台场地的对比研究,分析岛礁场地地震动场的分布规律。结果表明,岛礁场地的地震反应幅值与水平成层场地相比明显放大,其中礁顶中点附近加速度峰值放大系数可达1~1.5,角点附近可达1.5~2。向海坡坡度和礁坪宽度等地形因素及海水的动力耦合作用均对岛礁场地的地震反应有显著影响,采用一维土层和斜坡平台场地地震反应分析难以全面地刻画岛礁场地真实的地震动场分布特征。对于重要的岛礁工程场地,有必要进行可反映其真实力学特征的岛礁-海水耦合动力分析。
Here, comprehensively considering dynamic coupling action between reef and seawater, wave radiation effects at cutoff boundaries of solid and fluid media as well as seismic wave input, a 2-D seismic response analysis model for local layered reef-seawater system was established to study seismic field distribution laws of reef site by comparing with horizontal stratification site and slope platform site in land area. Results showed that seismic response amplitude of reef site is significantly amplified compared with that of horizontal layered site, the acceleration peak amplification coefficient near the middle point of reef top can reach 1-1.5, and that near the corner point can reach 1.5-2;topographic factors, such as, seaward slope and reef flat width, and reef-seawater dynamic coupled effect have significant influences on seismic response of island reef site, seismic response analyses of a 1-D soil layer and slope platform site are difficult to fully describe real distribution characteristics of seismic field of island reef site;for important reef engineering sites, it is necessary to perform a reef-seawater coupled dynamic analysis for the purpose of reflecting their real mechanical characteristics.
作者
宝鑫
刘晶波
王东洋
李述涛
王菲
BAO Xin;LIU Jingbo;WANG Dongyang;LI Shutao;WANG Fei(Department of Civil Engineering,Tsinghua University,Beijing 100084,China;China Nuclear Power Engineering Co.,Ltd.,Beijing 100840,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2020年第21期55-64,共10页
Journal of Vibration and Shock
基金
国家自然科学基金项目(51878384)
国家重点研发计划课题(2016YFC1402800)。
关键词
岛礁
海水
场地地震反应
地震波动输入
人工边界
流固耦合
reef
seawater
site seismic response
seismic wave input
artificial boundary
fluid-solid interaction
作者简介
第一作者:宝鑫,男,博士,助理研究员,1992年生;通信作者:刘晶波,男,博士,教授,1956年生。
