单个周边建筑对工业厂房屋面平均风压的气动干扰效应

Aerodynamic interference effect of single surrounding building on mean wind pressures on industrial building roof

工业厂房通常处于工业厂区内,受周边建筑的干扰,其表面风压分布与单个独立厂房不同,相邻建筑会对风荷载产生影响。基于单个厂房与两个串列厂房刚性模型风洞试验,给出了不同工况下屋面的平均风压,分析了屋盖横向、纵向端部与中部测点的平均风压分布规律,对比了不同串列距离条件下受扰厂房与独立厂房屋盖表面平均风压分布,探讨了平均风压系数干扰因子随风向角及干扰距离的变化规律。试验结果表明:不同风向角时,干扰效应截然不同;干扰效应存在临界风向角。临界风向角一般保持在30°～50°范围内,小于临界风向角时,干扰起放大效应;大于临界风向角时,干扰为遮挡效应。此外,运用最小二乘法拟合了干扰因子设计值实用计算式,为受扰厂房建筑屋盖表面风压的修正提供依据。

Due to the aerodynamic interference effects,wind pressure distributions on roofs of industrial buildings surrounded by similar buildings are different from those of isolated buildings.Wind tunnel tests for an industrial building interfered by a similar building were carried out and the data of mean pressures on its roof were obtained.The mean wind pressures distributions on the roof were studied for different test cases.The mean wind pressures for the interference cases were compared with those for isolated conditions.Meanwhile,the relations of mean pressures interference factors（IF） and wind direction and distance were explored.The results show that the interference effects vary with different wind directions.The critical wind angles are found to be about 30°~50°.The amplification effects are observed when the wind directions are less than critical wind angles;and the shielding effects are observed when the wind directions are larger than critical wind angles.Based on the test data,the formulae of design mean pressures interference factors（IFd） were established by fitting method of Levenberg-Marquart algorithm,which can provide references for the amendments to the loads on industrial buildings with interference.