混合梁矮塔斜拉桥设计与施工若干关键问题研究

发布时间：2018-01-12 11:44

本文关键词：混合梁矮塔斜拉桥设计与施工若干关键问题研究　出处：《长沙理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：矮塔斜拉桥是介于传统斜拉桥和连续梁桥或连续刚构桥之间的一种综合两者优势的桥梁结构形式。它具有斜拉桥的样式,但在结构受力特性、结构尺寸比例和斜拉索布置上,又与传统斜拉桥有一定的差别。目前刚性梁矮塔斜拉桥修建得较多,但梁高尺寸更小、主梁更加轻柔的柔性梁矮塔斜拉桥,更容易与环境相协调,更受人们青睐,更具有发展前景和推广意义。为此本文以世界上最大跨径混合梁矮塔斜拉桥——广东省潮惠高速公路榕江大桥为工程背景,围绕混合梁矮塔斜拉桥的界定、结构受力特性、结构参数分析、主梁施工方案和索梁锚固区应力分析展开了一系列的研究工作,结合Matlab符号计算功能推导了方便界定混合梁矮塔斜拉桥的结构特征参数计算公式,通过Midas/Civil有限元软件建立了考虑全桥施工全过程有限元仿真模型和结构参数分析模型,利用FBR_CAL_SUO有限元软件论证并比较了榕江大桥次边跨钢箱梁的施工方案,运用Midas/FEA对索梁锚固区进行了局部应力分析。本文主要研究内容如下:(1)文中简述了矮塔斜拉桥的发展状况,分析了混合梁矮塔斜拉桥的研究动态,提出了混合梁矮塔斜拉桥索梁活载比作为反映结构本质特征的重要评判指标,运用比拟梁等效的思路和Matlab符号计算功能推导了不同边界条件以及不同钢混主梁布置形式的混合梁矮塔斜拉桥索梁活载比计算公式,并分析了其与结构参数的关系。(2)根据多座实桥的统计对比分析,提出了具体的数值指标作为界定混合梁矮塔斜拉桥的分界点。索梁活载比小于0.5时为刚性梁矮塔斜拉桥,大于0.5时为柔性梁矮塔斜拉桥或者传统斜拉桥。(3)通过Midas/Civil有限元软件建立了榕江大桥全桥施工全过程的计算模型,计算并分析了各施工阶段和成桥运营阶段结构受力情况。根据榕江大桥的结构特点,运用Midas/Civil有限元软件建立了以主塔高度、主梁高度和辅助墩位置为结构变化参数的多个成桥阶段计算模型,论证了榕江大桥实际设计方案结构参数取值的合理性。(4)针对榕江大桥70m次边跨钢箱梁,拟定了桥面吊机悬拼法和支架法拼装两种施工方案,利用FBR_CAL_SUO有限元软件建立了两种施工方案的全桥施工全过程有限元分析模型,并从方案可行性、安全性、经济性和施工控制难易性等方面论证比较了两种施工方案,最后确定了推荐方案的施工张拉力和拼装标高。(5)针对性地选取了最不利荷载组合下索力最大以及斜拉索水平倾角最小的梁段为研究对象,通过Midas/FEA有限元软件对混合梁矮塔斜拉桥钢箱梁索梁锚固区进行了应力分析。
[Abstract]:Low tower cable-stayed bridge is a kind of bridge structure which combines the advantages of traditional cable-stayed bridge and continuous girder bridge or continuous rigid frame bridge. It has the style of cable-stayed bridge but the mechanical characteristics of the structure. The structure size ratio and cable arrangement are different from the traditional cable-stayed bridge. At present, the rigid beam low tower cable-stayed bridge is built more, but the beam height is smaller, and the main beam is more soft. Easier to coordinate with the environment and more popular. Therefore, this paper takes the world's largest span hybrid beam low tower cable-stayed bridge-the Rongjiang Bridge of Chaohui Expressway in Guangdong Province as the engineering background, and focuses on the definition of the hybrid beam short tower cable-stayed bridge. A series of research work has been carried out on the stress characteristics of the structure, the analysis of structural parameters, the construction scheme of the main beam and the stress analysis of the cable beam Anchorage zone. Based on the function of Matlab symbol calculation, the calculation formula of structural characteristic parameters of hybrid beam cable-stayed bridge with low tower is derived. The finite element simulation model and structural parameter analysis model considering the whole process of bridge construction are established by Midas/Civil finite element software. The construction scheme of secondary span steel box girder of Rongjiang Bridge is demonstrated and compared by using FBR_CAL_SUO finite element software. The local stress analysis of cable beam Anchorage zone is carried out by using Midas/FEA. The main contents of this paper are as follows: 1) the development of the cable-stayed bridge with low tower is briefly described in this paper. In this paper, the research trends of hybrid beam cable-stayed bridge with low tower are analyzed, and the ratio of live load of cable-stayed bridge with hybrid beam is proposed as an important index to reflect the essential characteristics of the structure. The formula for calculating the live load ratio of cable-stayed bridge with different boundary conditions and different layout forms of steel-concrete main beam is derived by using the idea of equivalent beam analogy and the function of Matlab symbol calculation. The relationship between the structure parameters and the structure parameters is analyzed. (2) based on the statistical analysis of many real bridges. The concrete numerical index is put forward as the dividing point to define the hybrid beam low tower cable-stayed bridge. When the live load ratio of cable beam is less than 0.5, the rigid beam low tower cable-stayed bridge is proposed. The calculation model of the whole construction process of the whole bridge of Rongjiang Bridge is established by Midas/Civil finite element software when the flexible beam with short tower cable-stayed bridge or the traditional cable-stayed bridge is more than 0.5. According to the structural characteristics of the Rongjiang Bridge, the height of the main tower is established by using Midas/Civil finite element software. The calculation model of the bridge stage is the height of the main beam and the position of the auxiliary pier. This paper demonstrates the rationality of the structural parameters of the actual design scheme of the Rongjiang Bridge. Aiming at the 70m span steel box girder of the Rong River Bridge, two construction schemes are proposed, one is the bridge deck crane assembly method and the other is the support method. The finite element analysis model of the whole construction process of two kinds of construction schemes is established by using FBR_CAL_SUO finite element software, and the feasibility and safety of the scheme are discussed. Two construction schemes are discussed and compared in terms of economy and construction control difficulty. Finally, the construction tensioning force and assembling elevation of the recommended scheme are determined. (5) the maximum cable force and the minimum horizontal inclination of the cable under the most unfavorable load combination are selected as the research object. The stress analysis of cable beam Anchorage zone of steel box girder of hybrid beam low tower cable-stayed bridge is carried out by Midas/FEA finite element software.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.27

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