大跨结构风模拟及其小波分析

WIND SIMULATION AND WAVELET ANALYSIS FOR LONG-SPAN SPATIAL STRUCTURE

大跨空间结构的风速模拟需要考虑风的时间和空间相关特性以及局部区域内风载的非高斯特性。从大跨度结构的风速风载特点入手 ,讨论了几种常用的风速功率谱并比较了两种风模拟方法———谐波迭加法与线性滤波器法的特点 ,阐述了最大熵值法及其应用。指出Hermite变换法用随机过程的偏度系数和峰度系数可推导出符合度较好的PDF函数。还介绍了一种新兴的数学工具———小波分析 ,因其“数学显微镜”的特性 ,小波分析在大跨度空间结构三维风速模型分析中有良好的应用前景。

In the wind simulation of long-span spatial structure, both time and spatial correlation and local non-Gaussian characters should be considered. The traits of wind velocity and loading considered different spectral density functions of wind are discussed and the results of two kinds of simulation approaches - wave superposition method and linear filter method are compared. The maximum entropy method and its application are also introduced. And Hermite transformation method is used in calculation of the approximate power density function in accordance with random process's skewness and kurtosis. A mathematic tool - wavelet analysis is introduced.