大跨铁路连续刚构桥等效风荷载研究

发布时间：2018-01-16 06:46

本文关键词：大跨铁路连续刚构桥等效风荷载研究　出处：《西南交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：大跨度连续刚构桥在成桥阶段刚度较大,具有较好的抗风性能,而由于其施工方法的特点,在施工阶段的最大悬臂状态下,其刚度较小,自然风会诱发结构的抖振响应,过大的结构响应会影响桥梁结构的施工及安全,这个阶段往往会成为连续刚构桥抗风性能的最不利状态。因此最大悬臂状态的风荷载计算就成为了桥梁设计的需要考虑的关键因素之一。等效风荷载在桥梁抗风领域的研究相对较少,而对连续刚构桥最大悬臂状态下的等效风荷载研究更是少之又少,本论文拟以既有的等效风荷载理论为基础,以乌龙江大桥及北东口水道特大桥为研究对象,对最大悬臂状态下的连续刚构桥等效风荷载进行研究。本文对连续刚构桥等效风荷载简化计算方法的研究主要有以下主要步骤：首先利用有限元软件ANSYS对研究对象在不同施工工况下的进行动力特性分析；其次利用节段模型风洞试验及数值计算的方法得到主梁典型断面及桥墩的静力系数；然后将等效风荷载分成平均风荷载、背景风荷载、惯性风荷载三部分,不同结构响应(悬臂端部位移、悬臂根部弯矩、桥墩墩底扭矩等)对应结构不同的影响函数及振型函数,依此对主梁及桥墩相应的等效风荷载简化计算方法进行研究,以期得到适用于工程应用的简化计算公式,并利用得到的简化计算公式对研究对象在最大双臂状态下的各响应进行计算；最后为验证简化计算公式的正确性,将简化计算结果同荷载--响应相关法计算结果(LRC)、规范方法加惯性风荷载计算结果相比较,进行误差分析,以得到简化计算公式的适用范围及精确程度。
[Abstract]:The stiffness of long-span continuous rigid frame bridge in the stage of completion is large and has good wind resistance. However, due to the characteristics of its construction method, the stiffness of the long-span continuous rigid frame bridge is smaller under the maximum cantilever state in the construction stage. The natural wind will induce the buffeting response of the structure, and the excessive structural response will affect the construction and safety of the bridge structure. The wind load calculation of the maximum cantilever state is one of the key factors to be considered in bridge design. There is relatively little research in the field. The research on the equivalent wind load of continuous rigid frame bridge under the maximum cantilever state is very rare. This paper is based on the existing equivalent wind load theory and takes the Wulong River Bridge and the Beidongkou Waterway Bridge as the research object. The equivalent wind load of continuous rigid frame bridge under the maximum cantilever state is studied. In this paper, the simplified calculation method of equivalent wind load of continuous rigid frame bridge is studied as follows:. Firstly, the finite element software ANSYS is used to analyze the dynamic characteristics of the research object under different construction conditions. Secondly, the static coefficients of typical sections and piers of the main beam are obtained by using the method of wind tunnel test and numerical calculation of segmental model. Then the equivalent wind load is divided into three parts: average wind load, background wind load and inertial wind load, and different structural responses (cantilever tip displacement, cantilever root bending moment). According to the different influence function and mode function of the bridge pier, the simplified equivalent wind load calculation method for the main beam and pier is studied. In order to obtain the simplified calculation formula suitable for engineering application, and use the simplified calculation formula to calculate the responses of the research object under the maximum two-arm state; Finally, in order to verify the correctness of the simplified calculation formula, the simplified calculation results are compared with the results of the load-response correlation method and the code method plus the inertial wind load calculation results, and the error analysis is carried out. The range of application and the degree of accuracy of the simplified formula are obtained.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.23;U441.2

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