围护结构非高斯风压极值估计的改进Hermite峰值因子法

Prediction of non-Gaussian wind pressure extreme value on claddings with modified Hermite peak factor method

为克服传统研究风压极值方法忽略带宽参数影响的不足和改进概率密度函数拟合效果,结合曲面拟合方法获得一种改进Hermite级数,提出了引入带宽参数的改进Hermite峰值因子法。采用改进Hermite峰值因子法和以往常用方法对开孔屋盖风压的峰值因子进行研究。结果表明:基于高斯分布的Davenport的峰值因子明显偏离非高斯峰值因子;忽略带宽参数的传统Hermite峰值因子法高估了风压的正负峰值因子;改进Hermite峰值因子法相应于传统Hermite方法和修正Hermite方法和Sadek-Simiu方法,估计的开孔屋盖风压的峰值因子最为安全准确,与观测峰值因子总体上最为接近。

For overcoming the defect that the traditional peak factor method can not consider the influence of bandwidth and get a better fitting performance of probability density function,a modified Hermite series is proposed based on the face fitting technique,and a modified Hermite peak factor method is proposed. Then the peak factors of wind pressures on an open roof are particularly studied by typical extreme value methods and modified Hermite peak factor method. It is shown that the results of Davenport method deviate from the results of non-Gaussian method significantly; the traditional Hermite method ignoring the influence of bandwidth over estimates the peak factors; the results of modified Hermite method are most close to the observed peak factors,comparing with traditional Hermite method,revised Hermite method and Sadek-Simiu method.