地震波频率非平稳对土石坝非线性结构响应影响研究  

Effect of frequency-domain nonstationarity of ground-motion on the nonlinear dynamic responses of embankment dams

作　　者：张饶 金峰[1] 黄杜若 刘宁[1] ZHANG Rao;JIN Feng;HUANG Duruo;LIU Ning(State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《水利学报》2022年第8期926-938,共13页Journal of Hydraulic Engineering

基　　金：国家自然科学基金面上项目(52179134);国家自然科学基金重大项目(52192670)。

摘　　要：地震动具有频率非平稳性的特征,对结构动力响应存在显著影响。本文发展基于小波包变换的人工地震波随机模拟方法,生成了一系列匹配目标加速度反应谱、能量累积过程和重要持时,同时具有特定频率非平稳性的人工地震波。以美国Success土石坝为例,研究了地震动频率非平稳性对土石坝非线性结构响应的影响。结果表明,控制模拟地震波的频率非平稳性,对土石坝结构响应有着更好的无偏估计,平稳地震波会低估坝体响应。Ground motion is a complex time series with nonstationarity in frequency-domain which has significant effect on the dynamic response of structures.In this paper,a stochastic simulation method of ground-motion is developed using the wavelet packet transform,and then a series of simulated ground motions that match the target spectral accelerations,but also match Arias intensity(I)build-up process,significant durations as well as nonstationarity characteristics are generated.Moreover,the effect of frequency-domain nonstationarity on the nonlinear dynamic responses of an embankment dam are investigated using these synthetic motions.Results show that the ground motions of which the frequency nonstationarity is controlled have a better unbiased estimation of the structural response,and stationary ground motions will underestimate the responses of the dam.

关 键 词：频率非平稳性 土石坝 非线性结构响应 人工地震波 小波包变换 

分 类 号：TV641[水利工程—水利水电工程]