世博轴索膜结构屋面风效应的监测分析

为深入研究体型复杂的索膜结构屋面在真实环境中的风压分布和风振特性,对世博轴索膜结构屋面开展了为期两年的风效应监测.通过分析2011年7月一次大风过程的监测数据,得到索膜结构屋面所处的风环境和风压分布特性,并将实测结果和风洞试验数据进行比较.分析结果表明:世博轴屋面来流风一侧以负风压为主,另一侧以正风压为主;来流风一侧边缘的脉动风压最大,另一侧的脉动风压较小;平均风压系数和脉动风压系数随屋面高度由高到低逐渐变小;随着风速的增大,平均风压系数基本保持不变;风压系数实测值略小于风洞试验值,两者分布趋势基本一致.

Monitoring and Analysis of Wind Effect on Membrane Roof of Expo Axis

In order to deeply investigate the wind pressure distribution and wind vibration characteristics of complex cable-membrane roof in real environment,a two-year wind effect monitoring of the Expo Axis was carried out.By analyzing the data recorded in a strong wind process in July,2011,the wind environment and wind pressure distribution of the roof were obtained and compared with those obtained by wind tunnel test.Analytical results indicate that(1) negative wind pressure predominates at the wind inflow side of the roof of the Expo Axis,while positive wind pressure predominates at the other side;(2) the pulse wind pressure on the edge of the wind inflow side is high,while that at the other side is relatively low;(3) both the average and the pulse wind pressure coefficients decrease with the roof height;(4) the average wind pressure coefficient is basically insensitive to the wind speed;and(5) though the wind pressure coefficient measured in real environment is less than that measured by wind tunnel test,they both possess similar distribution trend.