非平稳地震动过程模拟的谱表示-随机函数方法  

Simulation of non-stationary ground motion by spectral representation and random functions

作　　者：刘章军[1] 曾波[2] 吴林强[2] 

机构地区：[1]三峡大学土木与建筑学院,湖北宜昌443002 [2]三峡大学水利与环境学院,湖北宜昌443002

出　　处：《振动工程学报》2015年第3期411-417,共7页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51278282;50808113);三峡地区地质灾害与生态环境湖北省协同创新中心

摘　　要：在Priestley演变谱理论的基础上,采用随机函数的思想,建立了一类新的全非平稳过程模拟的谱表示-随机函数方法。在谱表示-随机函数方法中,实现了用2个基本随机变量即可精确表达原随机过程的目的。通过选取基本随机变量的离散代表点集,可以直接由演变功率谱密度函数生成具有给定赋得概率的代表性样本集合。以全非平稳地震动加速度过程的演变功率谱为例,验证了方法的有效性和优越性。最后,结合概率密度演化方法,进行了Duffing振子的随机地震反应分析与抗震可靠度计算。Based on the Priestleyts evolutionary spectral representation theory and the idea of random function, a hybrid spectral representation and random function approach is presented to simulate non-stationary stochastic processes. This approach uses two basic random variables to capture accurately the second-order statistics of the original stochastic process. Discrete representative points of the two basic random variables are selected, and representative sample functions with assigned probability are generated directly by the evolutionary power spectral density function. By means of the evolutionary power spectral density function of non-stationary ground motion acceleration process, the effectiveness and advantages of this approach are demonstrated. Finally, combining the probability density evolution method, the random dynamic response and reliability of the Duffing oscillator subjected to stochastic ground motions are investigated.

关 键 词：非平稳地震动 随机函数 演变功率谱 概率密度演化方法 DUFFING振子 

分 类 号：O324[理学—一般力学与力学基础] P315.9[理学—力学]