论文部分内容阅读
对两类典型的大跨度屋盖结构形式(球面屋盖和柱面屋盖)分别进行了超过1 000次的重复采样风洞试验,基于所获得的大量极值风压样本,运用广义极值理论和极大似然估计方法系统分析了极值风压的概率分布特征。研究表明:广义极值分布是描述极值风压概率分布的理想模型,多数区域极值风压符合极值Ⅲ型分布,少数尾流区测点极值风压符合极值Ⅰ型和Ⅱ型分布,且极值Ⅱ型分布区域对应的极值风压离散性更强。利用概率分析方法对传统的极值风压估算方法,即峰值因子法的保证率进行了检验,结果表明:峰值因子法无法给出具有一致保证率的极值风压分布,且低估了极值Ⅱ型分布区的最不利负压,误差率在20%~30%之间;应用概率分析方法可以获得具有确定保证率的极值风压,进而从概率意义上对局部极值风压的取值进行合理评估。
Two kinds of typical long-span roof structures (spherical roof and cylindrical roof) were tested by over 1000 repeated wind tunnel tests. Based on the large number of extreme pressure wind samples obtained, the generalized extreme value The theory and maximum likelihood estimation method systematically analyzed the probability distribution of extreme pressure. The results show that the generalized extreme value distribution is an ideal model for describing the extreme pressure distribution. The extreme pressure in most regions is in accordance with the extreme distribution of type Ⅲ. The extreme pressure of extreme wake meets the extreme values of type Ⅰ and type Ⅱ Distribution, and extreme type Ⅱ distribution area corresponding to extreme pressure wind pressure dispersion more. Probability analysis method is used to test the traditional method of extreme pressure assessment, that is, the peak factor method. The results show that the peak factor method can not give the extreme pressure distribution with uniform guarantee rate and underestimate the extreme value Ⅱ type distribution area of the most negative negative pressure, the error rate of 20% to 30%; the application of probability analysis method can be obtained with a guaranteed maximum rate of wind pressure, and then from the probability of the local extreme pressure Value for a reasonable assessment.