女儿墙对平屋面低矮建筑风荷载特性的影响

对平屋面低矮建筑进行1∶25缩尺刚性模型测压风洞试验,研究了无女儿墙工况和4种不同高度女儿墙的平屋面低矮建筑的风荷载分布规律。无女儿墙的平屋面主要承受风吸力作用,斜风向锥形涡诱导的最不利吸力区域为屋面迎风边缘角部区域,为全风向下最不利区域。女儿墙的存在可明显减小屋面的平均风吸力和极值风吸力,平均风吸力减小幅度可达150%,同时最不利平均风压系数和极小值风压系数的出现位置逐渐远离了屋面角部区域;随着女儿墙高度的增加,极值风吸力进一步减小,极值风压力增大,最大的极大值风压系数出现在尾流区;采取分区的方式给出了不同女儿墙高度的屋面体型系数建议取值。

Effect of parapet-wall on wind load of flat roof low-rise building

Wind tunnel test of 1∶25 scale rigid model for low-rise buildings with flat roofs was conducted to study the wind load distribution law of low-rise buildings with flat walls without parapet-wall and four parapet-wall heights. Flat roofs without parapet-wall are mainly subjected to wind suction. The most unfavorable suction area induced by the oblique wind conical vortex is the corner area of the windward edge of the roof, which is the most unfavorable area of the whole wind downward. The parapet-wall can significantly reduce the mean wind suction and extreme wind suction on the roof, and the average wind suction would be decreased of 150%, and the region with most unfavorable mean wind pressure coefficient and minimum wind pressure coefficient would gradually far away from the roof corner. With the increasing of the height of parapet-wall, the extreme wind suctions are reduced and extreme wind pressures increase, and the maximum wind pressure coefficients appear in the wake region. The block shape coefficients for different heights of parapet-wall were given by means of zoning.