线性随机结构的平稳随机响应

对于不仅结构参数具有随机性，而且外载是平稳随机激励的问题，给出了随机响应变异系数的计算方法。应用虚拟激励法先将随机荷载转化为确定性的简谐荷载，使双随机问题得以精确地转化为单随机问题进行分析。求解过程显著简化，而且包含了二种随机因素之间的耦合效应。用数值模拟法对方法的精度作了估计。

Stationary random responses of structures with stochastic parameters

For linear structures with uncertain parameters, the coefficients of variation of their stationary random responses are computed. The random excitations are first transformed into sinusoidal ones in terms of the pseudo excitation method (PEM), that turns the joint-random problem into a single random problem for which only structural parameters remain random, and thus the analysis is greatly simplified. A combination rule for coefficient of variation is derived in terms of which the combined coefficient of variation of the structure can be computed from the coefficient of variation of each random parameter provided the correlation matrix of these parameters is known. The method is efficient, and its precition has been justified by Monte-Carlo method. The coupling effect between two kinds of random factors has been involved.