大型多指廊屋盖风荷载非高斯特性风洞试验研究

Wind Tunnel Test Study of Non-Gaussian Characteristics of Wind Loads on a Large-scale Roof Structure with Multiple Corridors

基于我国大型机场航站楼(指廊间最大距离约1500 m)的刚性测压风洞试验,采用高阶统计量方法和柯莫哥罗夫-斯米尔诺夫假设检验方法(K-S法)分析了大型多指廊屋盖表面风压的非高斯特性以及周边建筑对屋盖表面风压分布特性的干扰效应.研究结果表明:周边建筑对屋盖表面风压分布特性的干扰效应总体不显著,极值负压略有减小;大型多指廊屋盖表面风压基本为负压,在屋檐及转角区域的负压值较其他区域更大.高阶统计量方法划分的非高斯区其结果比较分散,同一区域存在不连续情况,且部分区域划分结果对风向角不敏感,而K-S方法划分的非高斯区域连续且覆盖范围与风洞试验分析得到的风压分布规律比较吻合.最后,本研究的风洞试验结果表明:大型多指廊屋盖结构在迎风屋檐、转角等区域表现出明显的非高斯特性,应在我国大型屋盖结构风荷载规范中予以考虑,采用改进的峰值因子估计方法,并宜按非高斯性分区适度提高峰值因子取值.

Based on the wind tunnel test of the second largest-scale airport terminal in China(where the maximum space among the corridors is almost larger than 1,500m),this study investigates the aerodynamic interference effects of surrounding buildings on the wind pressure distribution characteristics of the complex large-scale roof with multiple corridors.Also,the non-Gaussian characteristics of wind pressures on the super large-scale roof structure is investigated by High-order Statistical Moment Method and Kolmogorov-Smirnov Method(K-S method).The results show that the effect of surrounding buildings on the wind pressure distribution characteristics is generally small,which is featured with slight decrease in the minimum negative pressure.Furthermore,the wind pressure on this roof is generally negative,in particular,the extreme values of negative pressures are observed on the leeward edge and roof corners due to the strong flow separation and vortices.In addition,the non-Gaussian regions distinguished by High-order Statistics Method are inconsistent in the same region,and the results are insensitive to the approaching wind directions.Meanwhile,the results of K-S method are quite consistent and are in good correspondence with the wind pressure distributions.Moreover,the large-scale roof with multiple corridors shows obviously distinguished non-Gaussian characteristics at the windward eave,corners and leeward areas.Therefore,it is of worth to consider the non-Gaussian characteristics in the wind load code of large-scale roof structures,and improve the peak factor estimate method and increase the peak factor in the non-Gaussian regions.