非高斯风压峰值因子估计:基于矩的转换过程法的对比研究

建筑围护结构抗风设计需要准确估计非高斯风压极值或者峰值因子。对于非高斯风压峰值因子估计，常用的基于矩的转换过程法有Hermite多项式模型（HPM）、Johnson转换模型（JTM）及平移广义对数正态分布（SGLD）模型。极值通常由母本概率密度函数（PDF）的尾部决定，现阶段对于三种模型基于相同前四阶矩预测的非高斯母本PDF尾部的差别尚不清楚，自然，对于这三种模型预测的极值或者峰值因子的差别尚无答案。为了探明三种模型的异同，从而提供一定的选取原则，该文就三种方法对非高斯风压峰值因子估计效果进行了系统的对比研究。首先从理论上对比了三种方法预测得到的母本PDF的差异和估计的峰值因子差别；其次，选用长时距风洞试验风压数据检验了三种方法对非高斯风压峰值因子的估计效果。结果表明在三种模型都适用的偏度和峰度组合范围内，HPM对非高斯风压峰值因子估计结果相比SGLD模型和JTM模型估计结果更准确。

A COMPARATIVE STUDY ON MOMENT-BASED TRANSLATION PROCESS METHODS FOR THE PEAK FACTOR ESTIMATION OF NON-GAUSSIAN WIND PRESSURES

Cladding design requires accurate estimation of the peak values or peak factors of non-Gaussian wind pressures.Among different translation process methods for estimating the peak factors,the moment-based Hermite polynomial model(HPM),moment-based Johnson transformation model(JTM)and moment-based shifted generalized lognormal distribution model(SGLD)are three commonly used ones.The peak value or peak factor is determined by the parent probability density function(PDF)tail.Currently,the differences of the predicted parent PDF of non-Gaussian process based on the same first four statistical moments by those models are not clear,which makes the selection of those models for peak value estimation ambiguous.To compare the differences of the three models and provide certain selection principles,this paper systematically compares the accuracy on the peak factor estimation of non-Gaussian wind pressures by the three methods.We numerically compare the difference of the predicted PDF and peak factors.Very long time wind pressures from a wind tunnel test are then used to validate the numerical observations and examine the accuracy of the predictions.The results showed that the HPM generally gave the most accurate estimations.