Collge of Civil Engineering, Taiyuan University of Technology
Hebei Key Laboratory of Earthquake Disaster Prevention and Risk Assessment
Engineering Research Center of Railway Environment Vibration and Noise, East China Jiaotong University
Xi’an University of Posts & Telecommunications

【目的】基于耦合的有限元法-解析法的海水-层状海床地基中Rayleigh波的传播特性以及土层动力响应研究不充分。【方法】将上覆沉积层和海水层分离成(二维杆系单元),将下覆半空间表面结点位移和节点力关系与整体刚度矩阵联立,建立波数-相速度(k-c)域内R波弥散特征方程及其二次特征值形式,探究R波的频散特性及不同阶数模态下场地的动力响应。【结果】结果表明,当海水层或上覆沉积层厚度较大时,基阶模态下的R波相速度相对较小,随频率的降低速率也更为明显,但海水层底部水平和竖向位移相对较大;海水动水压力随着频率的增加表现出先增后减的规律,并最终衰减至0;同一频率下,高阶模态的位移相对较大。

【Purposes】The study on Rayleigh wave propagation characteristics at the interface be⁃ tween seawater and layered seabed as well as the dynamic response of free field by the virtue of a coupled finite element and theoretical method is currently insufficent. 【Methods】Both the overlying sedimentary layer and the fluid layer were discretized into (one-dimensional, two-node, linear ele⁃ ments) according to standard finite-element techniques. The relation between the node displacement and node force on the surface of the underlying half-space was integrated into the global stiffness ma⁃ trix.The dispersion characteristic equation of Rayleigh wave in the wavenumber-phase velocity (k-c) domain was solved by transforming it into a quadratic eigenvalue problem. The multiple modes and dy⁃ namic response of the free field as well as the overlying fluid layer were obtained. 【Findings】The re⁃ sults show that a thicker seawater layer or sedimentary layer will result in a slower phase velocity un⁃ der the fundamental mode and a more obvious decreasing rate with the increase of frequency, while both horizontal and vertical displacements at the bottom of seawater are relatively larger. The hydrody⁃ namic pressure increases first and then decreases with increasing frequency, and finally decays to zero. Furthermore, with same frequencies the displacements under high order modes are relatively large.

中国博士后科学基金面上项目(2020M671960);河北省地震灾害防御与风险评价重点实验室开放基金资助项目(FZ213106);山西省基础研究基金面上项目(20210302123168);山西省省筹资金资助回国留学人员科研项目(2021-061);江西省博士后科研项目择优资助项目

王韫戬,章敏,王奇琪,等.Rayleigh波作用下海水-层状海床动力响应研究[J].太原理工大学学报,2025,56(2):288-297.

WANG Yunjian,ZHANG Min,WANG Qiqi,et al.Dynamic response of the seawater-layered seabed system sub⁃jected to Rayleigh waves[J].Journal of Taiyuan University of Technoloty,2025,56(2):288-297.