摘要
本文针对用于大跨度桥梁抖振时域分析的随机风场和Davenport相干函数的特点,对模拟多变量平稳随机过程的谐波合成法进行了改进.文中直接导出了互谱密度矩阵S(ω)的Cholesky分解的显式表达式;在不失精度的前提下,适当减少了部分余弦项;同时在模拟中运用了FFT技术,从而简化了计算过程,提高了计算速度.文章最后利用改进后的方法模拟了跨度为1000m的一座悬索桥的主梁随机风场,验证了方法的有效性.
In consideration of the characters of the stochastic wind field on long-span bridges and the Davenport's coherence function, an extended spectral representation method was proposed in this paper for simulating the stochastic wind field on long-span bridges. In this paper, an explicit expression of Cholesy's decomposition of the cross-spectral density matrixwas derived; some cosine functions were reasonably cut without sacrificing the accuracies; and the FFT technique was imposed into the algorithm. So the simulation can be easy and efficiently performed. According to this method, a stochastic wind field on the main beam of a suspended bridge with a span of 1000m was simulated so that the efficiency of the method was verified.
出处
《土木工程学报》
EI
CSCD
北大核心
1998年第3期72-79,共8页
China Civil Engineering Journal
