K-L分解在非平稳地震响应分析中的应用(英文)

Application of K-L Expansion for the Analysis of Non-stationary Seismic Response

介绍了一种非平稳地震激励下结构随机响应的分析方法。按照K-L分解理论,地震激励可以描述为一系列确定性函数与随机系数乘积的线性组合形式。对于线性结构,地震激励的每项K-L展开级数对应于一项结构响应。因此,任何确定性动力时程积分方法可以应用于求解与KL展开级数相对应的结构响应。这为商用有限元软件用于随机地震响应分析打开了方便之门,同时也有利于提高随机振动分析在实际工程中的应用。一个受均匀调制非平稳地震激励下的21层框架结构用于阐明这种方法。

The objective of the present work is introduced to a new procedure for random response analysis of structure subjected to non-stationary seismic excitation.According to Karhunen-Loeve（K-L）expansion theorem,which allows to represent random seismic random excitation as a series terms involving a complete set of deterministic functions with corresponding random coefficients.Clearly,for linear structures,each deterministic term of K-L expansion of the seismic excitation corresponds to a response.Therefore,any available deterministic dynamic integration scheme can be applied to calculate structural response associated with each term of K-L expansion of excitation process.This in turn opens the avenue for the use of commercial deterministic finite element packages in seismic random analysis,which may greatly enhance the acceptance and use of random analysis in engineering practices.A 21-story frame structure subjected to uniformly modulated non-stationary seismic excitation was used to demonstrate the procedure.