单点和多点荷载输入的虚拟激励法实用求解模式  

Practical solution mode of pseudo-excitation method corresponding to single and multiple point load input

作　　者：国巍[1,2] 余志武[1,2] 柳国环[3] 邬亮[1,2] 

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]高速铁路建造技术国家工程实验室,湖南长沙410075 [3]天津大学建筑工程学院,天津300072

出　　处：《建筑结构学报》2013年第7期11-19,共9页Journal of Building Structures

基　　金：国家自然科学基金项目(50938008;51108466);中国博士后科学基金项目(20110491277;2012T50707);中南大学博士后基金;长江学者和创新团队发展计划项目(IRT1296)

摘　　要：在实际工程中采用虚拟激励法(pseudo excitation method,PEM)往往需要编写复杂计算程序,为方便工程应用,建立了一种对应单点和多点荷载输入的虚拟激励法实用求解模式。考虑地震作用、风荷载等多种随机荷载,提取单点和多点荷载输入下计算结构虚拟响应的实用求解模式,并利用常规有限元分析软件的谐振稳态分析完成PEM核心计算,最后通过线性组合重新构建结构虚拟响应和功率谱密度函数的求解公式,从而在常规有限元分析软件中实现了PEM算法。由于采用建议方法可将PEM算法的核心计算交由有限元分析软件完成,在保持PEM高效准确计算优势的前提下显著提高了工作效率,避免了编写复杂计算程序,方便实际工程应用。通过两个典型数值算例验证了建议方法的正确性与有效性,并且指出其对于多种荷载工况的计算效率具有一定优势。Application of pseudo-excitation method（PEM） in practical engineering usually needs to complete complex calculation program.The practical solution mode for calculating structural pseudo response under single and multiple point load input was established.Considering several types of random loads such as earthquake,wind and so on,and extracting practical solution mode,the core calculation of PEM algorithm can be easily performed by harmonic steady analysis in general finite element analysis software.And then the pseudo response and power spectrum density function of structure are given by simple linear combination rule.As the core calculation of PEM algorithm is solved by software,the method proposed in this paper possesses both of computational efficiency and precision of the pseudo-excitation method.And stochastic analysis of practical engineering by PEM algorithm is greatly facilitated and programming is avoided.Finally,two numerical examples are given to verify the simplicity and validity of proposed method in this paper,and calculation efficiency of the method corresponding to multiple cases is also pointed out.

关 键 词：单点和多点荷载输入 虚拟激励法 实用求解模式 稳态分析 功率谱 

分 类 号：P315.9[天文地球—地震学]