平稳随机激励下线性随机结构动力响应分析  

DYNAMIC RESPONSE ANALYSIS OF LINEAR STOCHASTIC STRUCTURES UNDER STATIONARY RANDOM EXCITATION

作　　者：乔红威[1] 吕震宙[1] 

机构地区：[1]西北工业大学航空学院,西安710072

出　　处：《机械强度》2009年第2期190-194,共5页Journal of Mechanical Strength

基　　金：国家自然科学基金(NSFC10572117);航空科学基金(2007ZA53012);新世纪优秀人才支持计划(NCET-05-0868);863计划课题(2007AA04Z401)资助项目~~

摘　　要：对于外载是平稳随机激励的线性随机结构分析问题,在随机变量函数矩点估计和虚拟激励法的基础上,建立随机响应均方值特征参数的矩估计算法。应用虚拟激励法将随机载荷转化为确定性简谐载荷,计算确定性结构在平稳随机激励下响应的均方值,采用点估计方法分析平稳响应均方值的均值和方差,并计算响应均方值的变异系数,通过两个算例考察结构参数的随机性对结构响应均方值的影响。由于基于随机变量函数矩的点估计和虚拟激励法具有较高的效率和精度,因而所提方法具有一定的工程意义。For analysis of linear stochastic structure applied by stationary random excitation, the moment method, which is based on the point estimation of the function moment of basic random variables, is presented to obtain the characteristic values of the stationary random responses. In the presented method, the random excitations＇are first transformed into sinusoidal ones in terms of pseudo excitation method, then the mean square value of the structural response ruder the stationary excitations is computed, the mean value, variance and variation coefficient of the mean squared value of the structural response under the stationary excitations are developed by means of point estimate. The influences of the randomness of structural parameters on the randomness of the mean square value of the structural response are investigated by two examples. Due to the efficiency and precision of the pseudo excitation method and point estimate method, the presented method is valuable for engineering.

关 键 词：平稳随机激励 随机结构 随机响应 虚拟激励法 点估计 

分 类 号：O324[理学—一般力学与力学基础]