高墩多塔斜拉桥施工期风致振动与控制研究

发布时间：2019-04-22 18:06

【摘要】：现在斜拉桥建造技术日益成熟,斜拉桥正向着纤细、轻巧、跨径更大和多塔方向发展,对风的敏感性也不断增加。对于高墩多塔度斜拉桥而言,墩身过高而且结构刚度较小,在施工期风致抖振响应较大,可能引起桥梁结构安全问题、影响施工质量以及危及施工机械和人员的安全等问题,甚至引发桥毁事故。因此,开展高墩多塔斜拉桥施工期风致抖振响应与控制措施研究具有重要的工程应用价值和意义。本文以国内在建的赤石特大桥为工程背景,对高墩多塔斜拉桥施工期双悬臂状态进行抖振响应分析和抗风措施研究。论文主要工作内容如下： (1)简要介绍了国内外斜拉桥的发展历史,进而介绍了多塔斜拉桥的发展应用情况,并对大跨度桥梁抖振分析理论和斜拉桥施工期风致振动控制措施研究现状进行综述。 (2)采用谐波合成法并基于MATLAB软件编写了脉动风场模拟程序,模拟了赤石大桥桥塔、主梁关键节点的脉动风速,并与规范推荐的脉动风谱进行了比较,验证本文脉动风场模拟程序的有效性。 (3)采用大型有限元分析软件ANSYS对赤石大桥最大双悬臂状态进行结构动力特性分析。采用Davenport准定常抖振理论基于ANSYS软件实现了大跨度桥梁抖振时域分析,对赤石大桥原结构最大双悬臂状态风致抖振响应进行了计算,进而对其风致振动安全性进行评估。 (4)在综合调研国内外大跨度斜拉桥施工风致振动控制措施的基础上,结合赤石大桥实际特点,提出了“抗风缆和调质阻尼器(TMD)”混合控制的施工期抗风措施。对采取抗风措施后的最大双悬臂状态桥梁结构进行了风致抖振响应分析,并与原结构抖振响应数据进行比较,验证了本文采用的施工抗风措施对结构振动控制的有效性。 (5)设计并制作了几何缩尺比为1/200的全桥气弹模型,并加工制作了相应的抗风措施模型,分别对赤石大桥最大双悬臂状态原结构和采取抗风措施后的结构进行了紊流场风致振动试验研究,并与理论计算结果进行比较,验证了本文计算方法的可靠性,并且进一步检验了抗风措施的减振效果。
[Abstract]:Now the construction technology of cable-stayed bridge is becoming more and more mature. The cable-stayed bridge is developing towards the direction of slender, lightweight, larger span and more towers, and the sensitivity to wind is also increasing. For the cable-stayed bridge with high pier and multi-tower degree, the pier body is too high and the structural stiffness is small, and the wind-induced buffeting response is larger during the construction period, which may cause the bridge structure safety problems, affect the construction quality and endanger the safety of construction machinery and personnel, and so on. It even caused an accident of bridge destruction. Therefore, the research on wind-induced buffeting response and control measures during the construction of high-pier multi-tower cable-stayed bridge has important engineering application value and significance. In this paper, the buffeting response and wind resistance of high pier multi-tower cable-stayed bridge during construction are analyzed based on the engineering background of Chishi bridge under construction in China. The main contents of this paper are as follows: (1) the development history of cable-stayed bridges at home and abroad is briefly introduced, and then the development and application of multi-tower cable-stayed bridges are introduced. The theory of buffeting analysis of long-span bridges and the research status of wind-induced vibration control measures during the construction of cable-stayed bridges are reviewed. (2) the fluctuating wind velocity of bridge tower and main beam of Chishi Bridge is simulated by harmonic synthesis method and MATLAB software, and is compared with the fluctuating wind spectrum recommended by the code. The validity of the simulation program for fluctuating wind field in this paper is verified. (3) A large finite element analysis software ANSYS is used to analyze the structural dynamic characteristics of the maximum double cantilever state of Chishi Bridge. The time domain analysis of buffeting of long-span bridges is carried out by using Davenport quasi-constant buffeting theory based on ANSYS software. The wind-induced buffeting response of the original structure of Chishi Bridge is calculated and the wind-induced vibration safety is evaluated. (4) on the basis of comprehensive investigation on the wind-induced vibration control measures for the construction of long-span cable-stayed bridges at home and abroad, combined with the actual characteristics of the bridge, the wind resistance measures for the hybrid control of "wind-resistant cable and tuned-and-tempered damper (TMD)" are put forward during the construction period. The wind-induced buffeting response of the maximum double cantilever bridge structure with wind-resistant measures is analyzed and compared with the data of the buffeting response of the original structure. The effectiveness of the construction wind-resistant measures used in this paper to control the vibration of the structure is verified. (5) A full bridge Aeroelastic model with a geometric scale of 1? 200 is designed and fabricated, and the corresponding anti-wind model is made. The wind-induced vibration tests of the maximum double cantilever structure and the wind-resistant structure of the bridge are carried out, and the results are compared with the theoretical results to verify the reliability of the calculation method in this paper. Furthermore, the effect of anti-wind measures is further tested.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441.3;U448.27

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