以方形柱体为研究对象,通过3组仅缩尺比不同,其他指标完全相同的风洞试验测压模型,设置了不同周边建筑布置方式,研究了周边建筑与主体建筑在多种相对位置下阻塞效应对试验数据的影响。结果表明,迎风面风压系数受阻塞效应影响程度小于侧面和背风面,但当周边模型位于主体模型前方时,阻塞效应对迎风面均方根风压系数的影响仍不可忽略;侧面风压系数受阻塞效应影响程度最为显著(尤其当周边模型位于主体模型两侧时),且侧面上游测点平均风压受阻塞效应影响程度大于下游测点,而均方根风压系数则是下游受影响更明显;背风面风压系数受阻塞比的影响程度小于侧面,但当周边模型位于主体模型后方时,背风面下部测点受阻塞效应影响较为明显。整体来看,在同样的阻塞比下,不同周边建筑的摆放位置所造成的阻塞效应不相同,说明阻塞比这一整体指标不足以完全衡量出阻塞效应的严重程度,阻塞比的精细方法还有待建立。
The blocking effect caused by the surrounding locations on the experiment data was investigated by the square prism models with 3scale ratios and different arrangements of surrounding models.The experimental results showed that the influence degree of blocking effect on the wind pressure coefficients of the windward side is not as significant as those of the lateral and leeward sides.However,the influence of blocking effect on the root mean square wind pressure coefficients could not be ignored when the surroundings were located in front of the subject model.And the influence of the blocking effect on the wind pressure coefficients of lateral sides is the greatest,especially for the situation that the subject model located between the surroundings,and the blocking effect on the mean wind pressure coefficients of upstream points is greater than that on the downstream points,it is contrary for the root mean square wind pressure coefficients.Further more,the blocking effect on the wind pressure coefficients of leeward side is less significant than that of lateral sides,but the blocking effect on the wind pressure coefficients of the points near the bottom is obvious when the surroundings located behind the subject model.Moreover,the blocking ratio,as a global index,can not describe the blocking effect at different positions on a mode,it is necessary to establish a new reasonable method which can calculate the blocking ratio.