欢迎光临《计算力学学报》官方网站！

Method and program for simulating multi-support underground seismic motions in media-transition circular-arc site with partly filled water

DOI：10.7511/jslx20220324001

 作者 单位 李鑫洋 天津大学 水利工程仿真与安全国家重点实验室, 天津 300350天津大学 建筑工程学院, 天津 300350 柳国环 天津大学 水利工程仿真与安全国家重点实验室, 天津 300350天津大学 建筑工程学院, 天津 300350 费琦翔 天津大学 水利工程仿真与安全国家重点实验室, 天津 300350天津大学 建筑工程学院, 天津 300350

建立了同时引入土壤介质相变和半覆水圆弧地形因素的场地模型，并给出了地下多点地震动模拟的理论框架，开发了依据本文理论的程序并予以可靠性验证。首先，基于探明的波场分布得到了SV波入射半覆水圆弧相变场地的频域解；其次，获得依据频域解的场地传递函数并求解出地下自功率谱，建立了基于所得到的地下相干函数的地下互功率谱，由此构建出地下功率谱矩阵；最后，实现频域模型向时域信号转化（即多点地震动时程曲线），进而基于上述理论进行可视化程序开发。通过数值算例进一步阐明了本研究的意义，结果表明，（1）地下与地表多点地震动在能量分布上存在显著差异，说明了研究的必要性；（2）生成地震动的拟合功率谱和拟合相干函数与理论值吻合较好，表明了结果的合理性；（3）可视化程序界面简洁，参数输入及调整方便，后处理结果显示清晰，反映出程序的便捷及适用性。

A model was established by simultaneously considering the influencing factors of media transition and circular-arc terrain with partly filled water.The corresponding theoretical scheme for the simulation of multi-support underground seismic motions of the target site was presented and a program based on the above methodology was developed with its reliability verified.Firstly, the seismic scattering wavefields special for the site subjected to SV waves are illustrated in detail and the solution of ground response in frequency domain is obtained.Then, the transfer functions based on the solution are calculated and the underground auto-PSD can be expressed subsequently;the underground cross-PSD is given by the underground coherency model and the underground auto-PSD.Thus, the underground PSD matrix is assembled by combining the auto-PSD and cross-PSD.Finally, the multi-support underground accelerations in time domain are achieved by decomposing the underground PSD matrix.The GUI for the generation of multi-support underground seismic motions is further compiled.Numerical examples are conducted to highlight the significance of this study and the results show:(1) There exists a significant difference between the underground and ground seismic motions in frequency domain, which illustrates the necessity for the study.(2) The compatibility of simulating PSD and coherency function with corresponding target values is well expected, which demonstrates the rationality of the results.(3) GUI with flexible and adjustable parameter input is concise and the post-processing results are clear, which reflects the convenience and applicability of the program.