【作者】 田永胜；

【导师】 陈政清； 李寿英；

【作者基本信息】 湖南大学 ， 桥梁与隧道工程， 2009， 硕士

【摘要】 体育场悬挑雨篷属于大跨屋盖悬挑结构,同时也是大跨屋盖悬挑结构发展技术应用的主要载体,其作为一类新颖的结构形式,不仅具有大跨屋盖质量轻、柔度大、自振频率低等特点,而且由于悬挑的结构形式,致使当其处于风荷载的作用下时,屋盖上、下表面均要受到风的作用力,实际作用力为上、下表面的风压合力,成为典型的风敏感结构。本文以内蒙古乌海市奥林匹克中心体育场为研究背景,分别进行了只有单西挑篷,单东挑篷和同时有两挑篷三工况下的刚性模型风洞试验,基于试验数据,对两位置对立、跨度相仿、高度差别较大、而结构形状又具有代表性的看台挑篷之间的相互干扰效应从风荷载的平均风压系数,脉动风压系数,频率谱,挑篷总吸力及其根方差,结构动力响应等方面入手,对两挑篷间的相互干扰效应展开了系统的研究和深入的分析。分别建立了两挑篷的ANSYS有限元模型,基于测点风压时程,采用构造非定常气动力的方法,得到实际风场下的各测点压力时程,将此数据加载于ANSYS有限元模型,采用时程分析法进行了挑篷风致响应计算,进一步分析了挑篷在风致响应方面的干扰效应。并在对结构模态分析的基础上,基于各测点风荷载,构造广义力谱,采用了平稳随机激励下线性系统随机振动的模态叠加法编制了在频域上的动力计算程序SFSP。在程序的编制中,考虑了振型耦合项和力谱交叉项的影响,然后应用此程序分析了挑篷在脉动位移风致响方面的干扰效应,并与时程分析法计算的结果进行了比较。结果表明与时域法分析挑篷的脉动位移响应所得结果吻合较好,体育场挑篷频域法计算需考虑高阶模态的影响。更多还原

【Abstract】 The stadium canopy roof belong to long-span cantilever structure, and also is the main carrier of structure development technology application .As a new structure, it not only has the same characteristic as long-span structure, such as generally light, flexible and low damping, but also the upper and down surface of it’s roof will endure wind pressure meantime when it is in wind. So its actual pressure is the composition of its roof, and it is wind tenderness structure.Taking the stadium of Mongol Wuhai Olympic center as project background in this paper, by adopting wind tunnel test with synchronously measured pressure on the rigidity model with three cases, including west cantilever roof only, east cantilever roof only and double cantilever roves. As the test data, we have studied the interference effects between two coverings, with opposite position, similar spans, different altitude and the structures shape have the representation, including total wind suction, the distribution of average and fluctuating wind pressure coefficients, the wind pressure power spectrum of main test points and structure power response, etc. construct finite element model ANSYS of the two roves. Using the method of conformation No-Steady force to get the actual wind pressure, and then making use of the data, the modal and time domain analysis method to calculate the wind-induced response of these two roves. To analysis interference effect further. After analysis the structure modal, and base on wind pressure to calculate generalized force spectra, using method of modal superposition to developed the Frequency-domain dynamic computing program-SFSP under the circumstance of stationary random stimulation. In the process of developing the program, the effect of cross spectra and terms of modal are considered. Using the program to analyze the interference effect in the aspect of wind-induced response. Take the result to compare with the results that have been computed with Time domain analysis method. It indicated that: the conclusions that we gained from the method of Frequency-domain are the same with Time domain analysis method in the aspect of wind-induced response, and we should consider many models’effects if we adopt the method of Frequency-domain analysis.更多还原