大跨屋盖结构论文：大跨屋盖结构风荷载特性及抗风设计研究

大跨屋盖结构论文：大跨屋盖结构风荷载特性及抗风设计研究

大跨屋盖结构论文：大跨屋盖结构风荷载特性及抗风设计研究

【中文摘要】大跨屋盖结构一般是大型机场、车站或体育馆建筑的首选形式,而这类结构通常具有柔度大、阻尼小、质量轻等特点,风荷载成为作用在结构上的主要控制荷载,如何更精确的计算风荷载成为主导结构是否安全的最重要指标。由于大跨屋盖的结构形式不完全相同,规范中并没有统一的计算方法来确定其风荷载数值,而提供的体形系数和风振系数还不能囊括所有的大跨形式,因此,有必要对不同的大跨结构做深入的抗风分析和研究。本文结合青岛火车站站房屋盖的大跨结构形式,运用其刚性模型进行风洞试验,并建立有限元模型,从风压分布特性分析、风振系数的确定、静风荷载的加载等方面讨论结构对风荷载的响应,进而讨论结构的安全性。本文第二章详细分析了屋盖上不同分区的测点平均风压系数和脉动风压系数的分布情况,并选取典型测点进行分析,进而总结风压分布规律,得出了有关大跨度屋盖结构表面风压分布的一些具有共性的规律,得出各分区风压系数。本文第三章讨论了风致响应的计算方法。由风洞试验中得到的测点风压系数时程,经过一系列转换和修正,得到节点的脉动风荷载时程,通过对结构的前十阶振型的分析,讨论分区风振系数的取值,并最终得到屋盖整体的统一的风振系数。第四章分析了屋盖结构的静风响应,选取作用在结构上的两种不同的荷载,由前两章的数据经过比较和筛选,最确定结构上每榀组合钢在自重作用下和在自重与

静风组合荷载作用下的受力和变形,筛选最大应力和变形处与规范相关数值比较,最终确定结构的安全性。最后,对进一步的结构设计和分析提出建议,本文所得结论对结构的设计和施工有参考意义,可作为相似结构设计的参考。

【英文摘要】It is generally the first choice for

large-scale airport, station and gymnasium to use long-span roof structures with high flexibility, low damping and mass. Wind loading is usually a dominated one acting on structures, so it is the most important factor to judge the safety of structure under wind load accurately. However there is no general method of calculating wind load in the code because of configuration difference of long-span roof structures. In the other hand the shape coefficient and the gust response coefficient suggested by the code can’t embrace all forms of long-span structures, so it is necessary to analyze and discuss the wind resistance character of different long-span structures in depth.Based on the stiff model of long-span structure in Qingdao railway station, wind tunnel test is carried out and finite element model is established, this paper discusses the structure’s response for the wind and the structure’s safety by analyzing the wind pressure distribution character, confirming the gust response coefficient, and

exerting the static wind load.The second chapter of this paper discusses the distribution of mean wind pressure coefficients and fluctuating wind pressure coefficients in different areas of the roof, typical points for analyzing are selected, the regularity of wind pressure distribution is summarized, and partition wind pressure coefficients are obtained.The third chapter discusses the computing method of wind responsive. After a series of conversion and amendment, the nodes’fluctuating wind load history-time can be gotten from the measured wind pressure coefficient history-time, and the partition values of gust response coefficient are discussed by analyzing the first ten vibration modes, finally, the unified gust response coefficient of the whole roof is got, which is prepared for the next step of loading the static wind load.The forth chapter analyzes the response for static wind load on the roof, two different loads loading on the structure are selected, and the former two chapters’data are chosen and screened, then the carrying capability and deformation for the combined steel column of each rank under the dead load only and combination of the dead load and the wind load are confirmed, the maximum stress and deformation are chosen to compare with the code, finally the structure’s safety is assessed.Finally,