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基于缩尺比为1∶20的平屋面低矮房屋风洞试验模型,在A、B、C三类不同地貌条件下,以风向角为变量,研究地貌对低矮建筑屋面局部平均、脉动以及极值风压分布的影响。试验结果表明:屋面局部区域受风向角影响较大并呈现一定规律性。迎风屋面边沿区域以及角部区域受风向影响最为明显且风压大于其他区域;在斜风向45°风向角时,迎风屋面边沿区域角部测点平均、脉动、极值风压系数最大,为该类房屋最不利风向角;不同地貌对低矮房屋屋面平均风压系数影响较小,对脉动、极值风向系数影响较大。在0°、90°风向角时迎风屋面边沿平均风压系数受地貌影响较大,在斜风向下地貌的改变对屋面平均风压系数影响不大;随湍流度的增大屋面平均、脉动、极值风压系数绝对值也相应增大。
Based on the wind tunnel test model of low-rise flat roof with a scale ratio of 1:20, under the conditions of A, B and C, with the wind direction angle as the variable, the effects of topography on the local average, Influence of extreme pressure distribution. The test results show that the local area of the roof is greatly affected by the wind direction angle and shows a certain regularity. Wind direction is most obvious and the wind pressure is greater than other regions in the edge area and the corner area of the windward roof. At the 45 ° wind direction angle of the windward direction, the wind pressure at the edge of the windward roof area is the average, and the maximum wind pressure coefficient of pulsation and extreme value is The most unfavorable wind direction angle is the most unfavorable for the class houses. Different landforms have less influence on the average wind pressure coefficient of low-rise house roofs, but have a greater impact on the pulsation and extreme wind direction coefficient. At 0 ° and 90 ° wind direction angles, the mean wind pressure coefficient at the edge of the windward roof is greatly affected by the landform. The change of the geomorphology with the downward wind direction has little effect on the average wind pressure coefficient of the roof. With the increase of turbulence, The absolute value of the extreme pressure coefficient also increased accordingly.