贵州乌江大桥静动力特性研究及抗震分析

发布时间：2018-03-31 17:55

本文选题：悬索桥　切入点：PC板式主梁　出处：《长沙理工大学》2014年硕士论文

【摘要】：本文研究对象为贵州乌江大桥,该桥为两主塔塔顶高程相同且下塔柱高度不同的单跨PC板梁式悬索桥。为确保该桥的施工和成桥运营安全,对其进行进行施工过程、成桥状态的静力分析和动力特性研究,二者具有较强的实际意义,主要工作内容如下：(1)综述了PC板梁地锚式悬索桥构造形式及受力特点,并总结目前悬索桥动力研究状况。此外,对本文研究问题的提出进行阐述,并概括主要工作。(2)简要总结了悬索桥的主缆成桥线形计算方法,并详细阐述了其非线性影响因素和各类频率的估算方法。此外,综述了结构动力特性分析的内容和方法,并阐明悬索桥的有关动力特点且对有限位移静动力数值解法进行归纳,为下文的乌江大桥静动力研究提供理论基础。(3)采用有限元软件结合PC板梁悬索桥建模特点和乌江大桥施工特点建立了该桥的空问有限元模型,从而详尽地分析了该桥施工状态下,该桥构件成桥状态和施工过程中关键节点的内力和变位影响情况,并进行了主索鞍的顶推计算和主缆的抗滑验算等,验证了该桥的设计安全性。(4)对乌江大桥进行动力特性研究,得出其自振特性分析结果。对比分析了施工过程中该桥自振特性变化特点和不同吊装方案对其模态参数的影响,施工阶段的动力破坏；此外,探究了桩-土-结构间的作用、主梁的顺桥向约束刚度等对大桥动力特性的影响,后者比前者对动力特性的影响大；探究以上因素对该桥动力特性影响的同时,重点研究了塔顶高程相同两主塔下塔柱高度不同的桥塔构型对该桥动力性能的影响,对高低塔柱的高度设计提出取值建议,从而达到合理配置塔柱刚度获得良好的动力特性的目的。(5)对该桥运用反应谱法和时程分析法对其成桥状态进行地震响应对比分析,得出两种分析法对应的内力和位移响应结果的差异。最后采用时程分析法,对比单向、多向多组合地震一致正交激励对该桥的影响,从而得出该桥较为全面抗震结果,对该桥的抗震验算方法提出建议,确保大桥抗震可靠。
[Abstract]:The research object of this paper is the Wujiang Bridge in Guizhou, which is a single span PC-plate girder suspension bridge with the same top height of the two main towers and different lower tower column height.In order to ensure the construction and operation safety of the bridge, it is of great practical significance to carry out the construction process, the static analysis and the study of the dynamic characteristics of the completed bridge.The main work is as follows: (1) the structure and mechanical characteristics of PC slab girder ground anchor suspension bridge are summarized, and the current dynamic research status of suspension bridge is summarized.In addition, the contents and methods of structural dynamic characteristic analysis are summarized, and the related dynamic characteristics of suspension bridge are expounded, and the finite displacement static and dynamic numerical solution is summarized.This paper provides a theoretical basis for the following static and dynamic study of Wujiang Bridge. (3) the empty finite element model of Wujiang Bridge is established by using finite element software combined with the modeling characteristics of PC-slab girder suspension bridge and the construction characteristics of Wujiang Bridge.The design safety of the bridge is verified. 4) the dynamic characteristics of Wujiang Bridge are studied, and the analysis results of its natural vibration characteristics are obtained.The characteristics of natural vibration characteristics of the bridge during construction and the influence of different hoisting schemes on its modal parameters and dynamic failure in construction stage are compared and analyzed, in addition, the role of pile-soil-structure is explored.The influence of the restrained stiffness of the main girder on the dynamic characteristics of the bridge is greater than that of the former, and the influence of the above factors on the dynamic characteristics of the bridge is discussed.The influence of different tower configuration on the dynamic performance of the bridge with the same tower top height and different tower height under the main tower is studied, and suggestions for the height design of the high and low tower columns are put forward.In order to achieve the goal of reasonably allocating the column stiffness to obtain good dynamic characteristics, the response spectrum method and time history analysis method are used to compare and analyze the seismic response of the bridge.The difference of internal force and displacement response between the two methods is obtained.Finally, time history analysis method is used to compare the effect of unidirectional and multi-direction combined earthquakes on the bridge, so as to obtain the more comprehensive seismic results of the bridge, and put forward some suggestions for the seismic checking method of the bridge to ensure the seismic reliability of the bridge.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441;U448.25

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