大型堆料库顶棚结构设计风荷载的确定

Study on the wind load for large-scale storehouse

大型堆料库的顶棚结构跨度大、外形特殊,其风载体型系数需通过风洞模型试验进行测定。以某大型堆料库顶棚结构为研究对象,通过风洞模型测压试验,测量出其在模拟大气边界层紊流下的风压系数分布和风载体型系数,考虑了内部堆料、端防风网等对其风压系数分布的影响,根据试验结果以及国内外相关文献,分析讨论了其考虑动力影响的阵风影响系数,从而确定了其结构设计时的风荷载。分析表明,该类大型结构的风压分布和体型系数,受风向角、防风网设置与否影响很大,在风荷载计算时,应考虑风载沿加载长度的相关性影响,并根据结构特点及设计特点选取不同的阵风影响系数。

The span of vault of large-scale storehouse is long and its topography is exceptional.The shape coefficient for the storehouse must be gained by the wind tunnel test.In this paper,a large-scale storehouse,which span is 2x100 m,is taken as case studied.The wind tunnel test for its model is done in the turbulent boundary layer,which simulated the natural wind over typical open-country.The distribution of wind pressures on the storehouse is measured by the model.The effects on the wind load by the internal stuff and end anti-wind net is investigated.Basing on the analysis for the results from wind tunnel test and referring the national standards of several country,the dynamic wind loads is get and the gust loading factor is calculated.It is shown,the distribution of wind pressures and the shape coefficient from wind tunnel test is affect by wind direction and the anti-wind net.The gust loading factor is interrelated with the character of structure and design feature.And to calculate the wind load,the wind velocity correlation along longitude must be consider.