孙建龙

（中铁第一勘察设计院集团有限公司，西安 710043）

 

［摘要］对3个大型火车站雨棚进行风洞测压试验，分析结果表明开放式雨棚受站房影响较大，在不同风向下可能形成“上吸下顶”的受力特征，造成局部风压幅值的增加。由于风压分布不均匀和尾流区范围大等原因，体量较大的雨棚平均整体风吸力系数在-0.25左右，远小于小体量的雨棚，且基底竖向反力的变化范围也比较小。结合测压时程，采用广义坐标合成法计算了雨棚的风振响应，着重指出由于雨棚整体风压基本上是风吸力，因而对应最大竖向反力的风振系数可能出现负值或很高的正值，导致得出的等效静风荷载不合理，此时采用附加风振力法可得出更符合实际情况的等效静风荷载。

［关键词］雨棚；风洞试验；广义坐标合成法；风振系数；等效静风荷载；附加风振力

中图分类号：TU312+.1        文献标识码：A        文章编号：1002-848X(2013)04-0088-06

 

Sun Jianlong

（China Railway First Survey and Design Institute Group Ltd., Xi′an 710043, China）

 

Abstract: It was demonstrated that the wind pressure on the canopy was affected significantly by the station buildings through wind tunnel tests on three large railway stations. The local negative pressure was strengthened by the positive pressure on the underside of the canopy under different wind directions. The average overall wind suction coefficient of the larger canopy was around -0.25 which is much less than that of the smaller canopy, and change range of the vertical reaction force in the bottom was relatively small, due to the non-uniformity pressure distribution and a large area governed by the wake flow. The wind-induced vibration responses were obtained by the generalized coordinates synthesis method on the basis of the wind pressure time history. It was shown particularly that the wind-induced vibration factor corresponding to the maximum vertical reaction force could be a negative value or a rather high positive value as the overall wind pressure of the canopy is basically a wind suction. These unusual factors accordingly led to unreasonable equivalent static wind load. The additional wind-induced vibration force method was suggested to be applied for deriving the equivalent static wind load in such situation.

Keywords: canopy; wind tunnel test; generalized coordinates synthesis method; wind-induced vibration factor; equivalent static wind load; additional wind-induced vibration force

作者简介：孙建龙，硕士，高级工程师，Email:tyysjl03@sina.com。

 

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