有相位差非平稳随机激励下系统的响应

线性系统在有相位差非平稳随机激励下的响应是工程研究中十分有意义的问题。本文在用有限元离散建立系统方程的基础上，在状态空间应用复模态理论推导了线性系统受非平稳随机激励的位移的均方响应，且给出了减缩模态准确地处理非经典阻尼的计算形式和多相位调制白噪声激励下的系统相关响应的解析表达式。该方法可以方便地处理桥梁结构或其它结构的集中阻尼问题。对比算例表明，在工程设计中考虑相位差的影响是十分必要的。

Time dependent correlation function of linear systems excited by non-stationary spatially varying excitation

The response of unsymmetric linear multi degree of freedom systems undergoing non stationary spatially varying random excitation was investigated via complex modal theory, for the case when the random process, but not its amplitude and phase, was the same everywhere. In this paper, the reduced modal form was presented, so the method can be used in large scale systems. By adopting complex mode analysis, the method can be used to classical damping linear system as well as non classical linear system. General explicit expressions for the elements of the time dependent correlation function matrix were derived which could be used to simulate different real random processes more accurately. Numerical examples were given and compared. It shows that the effect of spatially varying is important.