基于虚拟激励法的大跨度桥梁非平稳随机振动分析闭合解  

Closed solution for non-stationary random vibration analysis of long-span bridge based on pseudo excitation method

作　　者：赵岩[1,2] 张亚辉 林家浩[1] ZHAO Yan;ZHANG Ya-hui;LIN Jia-hao(State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial Equipment,Dalian University of Technology,Dalian 116023,China;Ningbo Research Institute of Dalian University of Technology,Ningbo 315016,China)

机构地区：[1]大连理工大学力学与航空航天学院工业装备结构分析优化与CAE软件全国重点实验室,大连116023 [2]大连理工大学宁波研究院,宁波315016

出　　处：《计算力学学报》2024年第1期202-208,共7页Chinese Journal of Computational Mechanics

基　　金：国家自然科学基金(11772084,U1906233);国家重点研发计划(2017YFC0307203);中央高校基础研究经费(DUT22ZD209)资助项目.

摘　　要：针对大跨度结构考虑地面空间运动的非一致地震响应分析问题,结合虚拟激励法,应用傅里叶分析建立了结构非平稳随机振动响应演变功率谱分析的频域方法。建立的方法完全基于频域执行,给出了响应演变功率谱的闭合解表达式。由于实现了确定性调制过程与随机过程的有效分离,应用离散傅里叶变换进行计算不需要较高的采样分析频率就可以获得较好精度的数值结果。数值算例研究了某斜拉桥的考虑地面运动空间效应非平稳随机地震响应,与通常时频分析方法进行对比,验证了本文频域方法的正确性和有效性。In order to solve the problem of non-uniform seismic response analysis considering the motion of ground space for calculating long-span structures,combined with the pseudo-excitation method,a frequency domain method for calculating the evolution of power spectrum of non-stationary random vibration response of structures is established by using Fourier analysis.The proposed method is based entirely on frequency domain execution,and a closed form solution expression for the response evolution power spectrum is given.Due to the effective separation of the deterministic modulation process and the stochastic process,the discrete Fourier transform is used to obtain numerical results with good accuracy without high sampling and analysis frequency.Numerical examples are given to study the non-stationary random seismic response of a cable-stayed bridge considering the spatial effect of ground motion,and the correctness and effectiveness of the established frequency domain method are verified by comparison with the conventional time-frequency analysis method.

关 键 词：多点输入 非平稳 随机振动 虚拟激励法 闭合解 

分 类 号：O324[理学—一般力学与力学基础]