水平成层海床场地非线性地震反应的流⁃固弱耦合分析  

Fluid⁃solid weak coupling analysis of nonlinear seismic response at layered seabed sites

作　　者：范宏飞 王彦臻 陈炜昀 陈国兴[1,2] 赵凯 FAN Hongfei;WANG Yanzhen;CHEN Weiyun;CHEN Guoxing;ZHAO Kai(Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 210009,China;Civil Engineering and Earthquake Disaster Prevention Center of Jiangsu Province,Nanjing 210009,China;School of Civil Engineering,Sun Yat-sen University,Guangzhou 510275,China;Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai),Zhuhai 519080,China)

机构地区：[1]南京工业大学岩土工程研究所,江苏南京210009 [2]江苏省土木工程防震技术研究中心,江苏南京210009 [3]中山大学土木工程学院,广东广州510275 [4]南方海洋科学与工程广东省实验室(珠海),广东珠海519080

出　　处：《振动工程学报》2025年第4期849-859,共11页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51978334);国家重点研发计划项目(2017YFC1500403)。

摘　　要：海床场地地震反应分析是建设海洋工程的重要先期工作。以琼州海峡海底拟建隧道沿线4个典型钻孔剖面为研究对象,基于一种流⁃固弱耦合分析法模拟海水⁃海床之间的相互作用,采用广义non⁃Masing本构模型(DCZ模型)模拟软弱海床土的动力非线性特性,探讨海水、软弱海床沉积及基岩地震动特性对海床场地的地震反应的影响。主要结论为:海水对海床地震运动的抑制效果仅存在于海床浅层范围(<50 m),且对竖向地震反应的抑制效果优于水平向;海水对海床地表地震运动的抑制效果以及海床地震反应“高频抑制、低频放大”的频响现象与海水水深呈“正相关”;数值计算所得的水平向、竖向加速度β谱均值线在数个周期范围内高于陆域规范设计谱,表明海水、海床软弱沉积对海洋工程抗震产生的不利影响不可忽略。The analysis of seismic response at seabed sites is a crucial initial step in marine engineering construction.In this study,a fluid-solid weak coupling model is employed to replicate the interaction between seawater and the seabed.Specifically,four representative borehole sections along the proposed tunnel at Qiongzhou strait are chosen to investigate the influence induced by seawater,soft sediments,and bedrock earthquake motion on the seismic responses of the seabed site.A generalized non-Masing constitutive model(DCZ model)is utilized to account for the dynamic nonlinearity of the seabed soft soil.The findings indicate that the suppression effect of seawater on seismic motion in the seabed is limited to depths shallower than 50 m.Furthermore,the suppression effect is more pronounced in the vertical direction compared to the horizontal direction.Additionally,there is a positive correlation between the suppression effect of seawater on seismic motion at the seabed surface and the frequency response phenomenon characterized by high frequency suppression and low frequency amplification in the seabed seismic response.This correlation is influenced by the depth of the seawater.The mean lines of the horizontal and vertical spectrum β obtained by numerical calculation are higher than the design spectrum in the land code in several period ranges,and the possibility of adverse effects induced by seawater and seabed soft sedimentation on the seismic resistance of marine structures should be considered.

关 键 词：海床场地 非线性地震反应 流⁃固弱耦合模型 琼州海峡 土的非线性 

分 类 号：TU433[建筑科学—岩土工程]