基于随机相位差谱的全非平稳地震动建模  

Modeling of fully non-stationary ground motions based on random phase difference spectrum

作　　者：吕庆霞 刘章军 姜云木 刘子心 LV Qingxia;LIU Zhangjun;JIANG Yunmu;LIU Zixin(School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan 430074,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian 116024,China;Key Laboratory of Building Collapse Mechanism and Disaster Prevention,Institute of Disaster Prevention,China Earthquake Administration,Sanhe 065201,China)

机构地区：[1]武汉工程大学土木工程与建筑学院,湖北武汉430074 [2]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [3]防灾科技学院中国地震局建筑物破坏机理与防御重点实验室,河北三河065201

出　　处：《地震工程与工程振动》2024年第5期139-148,共10页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(51978543,52108444);武汉工程大学研究生教育创新基金项目(CX2022210)。

摘　　要：为合理表征地震动过程的全非平稳性和随机性,发展了一类基于相位差谱和功率谱结合的随机地震动模型。首先,阐明了相位差与地震动全非平稳性的关系,并利用实测强震记录,进行相位差谱模型参数的识别及统计分析。其次,采用确定性和随机性参数的功率谱模型,分别获得确定性参数的取值以及随机性参数的归一化最优概率分布。最后,通过选取基本随机参数的代表性点集,获得相应的地震动加速度代表性时程集合。研究结果表明:仅需2个或4个基本随机变量即可模拟具有自然变异性及丰富概率信息的地震动加速度过程,且模拟所得的加速度反应谱与实测强震记录拟合良好,为应用概率密度演化理论进行复杂工程结构的随机地震反应及抗震可靠性精细化分析奠定基础。In order to reasonably represent the fully non-stationarity and randomness of the land acquisition seismic process,a random seismic model based on a combination of phase difference spectrum and power spectrum has been developed.Firstly,the relationship between phase difference and non-stationarity of seismic ground motion was elucidated,and the identification and statistical analysis of phase difference spectrum model parameters were carried out using strong motion records.Secondly,power spectrum models with deterministic and stochastic parameters were used to obtain the values of deterministic parameters and the normalized optimal probability distribution of stochastic parameters,respectively.Finally,by selecting representative point sets of basic random parameters,the corresponding representative time history set of seismic acceleration was obtained.The calculation example shows that the method in this paper only requires 2 or 4 basic random variables to simulate the seismic acceleration process with natural variability and rich probability information,and the simulated acceleration response spectrum fits well with the strong motion records.The study lays the foundation for applying probability density evolution theory to the random seismic response and seismic reliability refinement analysis of complex engineering structures.

关 键 词：随机相位差谱 功率谱 随机参数 参数识别 实测强震记录 

分 类 号：P315.9[天文地球—地震学] TU311.3[天文地球—固体地球物理学]