不同排列方式平屋面建筑群极值风荷载干扰效应影响研究

Investigation on interference effects on peak wind loads on a group of buildings with flat roof under different arrangements

通过风洞试验,采用单因素轮换法,研究了建筑物排数、列数及面积密度对平屋面低矮建筑群各位置建筑物的屋面极值风压系数干扰效应的影响规律。试验结果表明：屋面大部分区域极值风荷载干扰效应以遮挡效应为主,中心建筑物的屋面各区域、边缘和角部建筑物的角部和中心屋面区域遮挡效应尤为显著,屋面边缘中间区域出现了放大效应,最大增幅达到14%;增加建筑物排数或列数,对角部和边缘建筑物影响较大,其屋面角部和中心区域极值风压缩减效应进一步增强;3排3列建筑群中,中心建筑物屋面各区以及角部和边缘建筑物靠近建筑群中心的屋面角部区域极值风压均对建筑面积密度较为敏感,干扰因子随建筑面积密度增加而线性减小,比例系数接近-1. 0,而角部建筑物和边缘建筑物中远离建筑群中心的屋面角部区域极值风压对建筑面积密度并不敏感。

Fluctuating wind pressures on a group of low-rise buildings with flat roofs were measured by wind tunnel test, and the influences of building row, column and building area density on the interference effects of peak wind pressure on the roof zone of the buildings located at the corner, edge and center of the building group were investigated by a single factor rotation method. The results demonstrate that shielding effects on peak wind loads of most roof zones are noticeable. The shielding effects are particularly significant for the entire roof zones of the center buildings and for the comer and central roof zones of the corner and edge buildings, in addition, amplification effects occur at the edge middle roof zones, where the largest increase reaches 14%. Increasing the building row or column has more significant effects on comer and edge building, where the shielding effects of the comer and center roof zones are further amplified. For the building group with three rows and three columns, the interference factors of all the roof zones of the center building, and those of the comer roof zones （near the building group center） of the comer and edge buildings, are more sensitive to the building area density, and the values decrease linearly （proportional coefficient is close to - 1.0） with an increase in the building area density. In contrast, the interference factors of the comer roof zones away from the building group center for the comer and edge buildings are less sensitive to the building area density.