【作者】 王吉民；

【导师】 孙炳楠； 楼文娟；

【作者基本信息】 浙江大学 ， 结构工程， 2001， 博士

【摘要】 薄膜结构是二十世纪后半期逐渐发展起来的大跨空间结构体系。从薄膜结构诞生的那天起，人们对这类新型建筑结构的研究一直没有间断过，但从大量的研究成果来看主要集中在薄膜结构的找形、剪裁、施工以及静荷载的分析，很少涉及到风振动力特性研究。然而从薄膜结构这类大跨空间柔性结构的受力分析来看，边界层内高湍流度风场中的风流经薄膜屋面时，会在薄膜结构的大部分区域产生强大的吸力，并在流体的粘性扩散中、尾迹中形成旋涡的脱落和对流过程，由这些包括涡激振动力在内的风荷载是薄膜结构的主要控制荷载。因此，深入研究薄膜结构的风荷载特性以及进行风振、涡激振动方面的研究，不仅具有较深的学术研究价值，而且具有重要的工程应用价值。 本文从风洞模型试验出发，对薄膜结构上的风压特性进行了较深入的研究，并从理论方面对作用在屋盖上的附加空气质量进行了详细的分析，对薄膜结构的风致振动、涡激振动的机理以及风振响应进行了较为系统的研究，取得了一些有意义的结论。 在风洞试验方面，设计制作了双坡屋面结构在四周封闭、四周敞开和突然开孔各种不同情况下的刚性模型和气动弹性模型，解决了刚性模型同时测定上下表面风压而又不影响周围风场的模型制作问题；建立并完善了考虑弗劳德数等一系列相似准则的气动弹性模型的设计制作方法，验证了风洞模型和实物原型在各有关参数之间应满足的相似准则，从而使风洞试验结果能直接应用于工程实践。 在风振响应分析方面采用理论与试验相结合的方法，即利用刚性模型风洞试验获得的在各种不同情况下屋面各节点的动态风压时程作为风荷载数据，对薄膜结构的凤振响应进行有限元时程分析，并与气弹模型的风振响应试验结果进行对比，两者的差别较小，能够满足工程应用的要求。这表明此方法的荷载数据直接来源于试验，具有较高的可靠性，能够避免准定常假设在大跨薄膜结构的风振响应分析中产生的误差。 以随机过程模拟技术中的线性滤波器法为理论基础，利用自回归模型（AR法）模拟了作用在薄膜结构上的风速时程，进而转换为作用于结构上的脉动风荷载时程。针对薄膜结构的振动和受力特点，详细推导了非定常流中作用在薄膜结构上的附加空气质量的计算公式，并得到了理论解。在总荷载中计入了由附加空气质量转换而来的惯性荷载并进行时程计算，对薄膜结构的涡激振动响应进行了研究，得到一些重要的结论。更多还原

【Abstract】 From the second half of the last century, membrane structures have attracted great attention because of their novel shape and reasonable behavior. Many studies of membrane structures were focused on the form-finding, cutting patterns, static analyses and construction, rarely involved in the field of studying its characteristics of wind-induced vibration. From the view of structure analyses, great wind turbulence in the boundary layer makes such large-span flexible roofs as membrane structures generate powerful lift in the large section. Vortex and the convection are formed in the process of viscosity diffusion and fluid wake. The wind load including vortex-induced vibration is the main load to those kinds of structures. Studies on the characteristics of wind-induced and vortex-induced vibration to membrane structures have not only the value of academic research but also that of significant practical engineering.In the paper the characteristics of wind pressure of membrane structures is studied thoroughly with the help of wind tunnel model experiment. Added air mass on the membrane roof is analyzed in detail. Some meaningful results are obtained for mechanism of wind-induced and vortex-induced vibration of membrane structures by systematical studies about them.In the matter of wind tunnel experiments, the rigid and aeroelastic model for double-slop membrane structures with seal and opening on all sides, or opening a hole suddenly, are designed. The question that the tubes, connected to pressure taps, which measure the wind pressure on both upper and under surface of rigid models, do not influence wind field around building, especially under roof, is solved commendably. A series of analogy parameters such as Froude number are considered and used for aeroelastic model design. These analogy parameters between model and prototype are verified, and make possible that the results from model test in the wind tunnel can be applied to prototype directly.Wind-induced vibration is analyzed based on wind tunnel test and theoretical analysis. According to the data gained from the wind tunnel test in the different circumstance, the structures are analyzed by using finite element method in time domain. The comparative analyses prove that the results from the theoretical analysis have good agreement with those from wind tunnel experiment. It enunciates that this method turns out high reliability because load data are obtained from test directly, and avoids deviation from theoretical calculation based on the quasi-static assumption in the studies of wind-induced vibration of membrane structures.Based on the linear filter technology of random process, artificial wind speed processes are generated with the autogressive-type simulation methods, which consider time and spatial correlativity, and can be converted into time history record of fluctuating wind pressure. The formula to calculate additional air mass on the membrane in unsteady flows is performed and theoretical equation is provided. The vortex-induced vibration of membrane structures considered from the additional air mass is discussed and some important results are obtained.更多还原