高速铁路连续索张弦主梁矮塔斜拉桥结构体系研究

发布时间：2018-06-13 17:41

本文选题：连续索 + 张弦主梁矮塔斜拉桥　；参考：《清华大学》2015年硕士论文

【摘要】：连续索张弦主梁矮塔斜拉桥是基于矮塔斜拉桥进行性能改进的一种结构体系,亦属于组合索支撑体系的扩展。其具有主梁截面小、结构自重轻、活载刚度大、动力性能好等特点,使其应用于对刚度要求十分严格的高速铁路桥梁成为可能。该新型结构体系此前的研究多侧重于公路桥梁且缺乏较系统的分析,尚未有针对铁路桥梁的系统研究。本文在前人研究的基础上,对连续索张弦主梁矮塔斜拉桥进行结构布置,并针对其在高速铁路荷载作用下结构刚度、主梁内力、列车作用下动力性能等方面的基本力学性能进行研究,并对影响结构性能的参数进行分析,总结了合理的参数范围,为工程应用提供参考。主要研究内容及成果如下:1、对高速铁路连续索张弦主梁矮塔斜拉桥的基本结构构成、索—杆单元进行布置。采用基于影响矩阵原理的未知荷载系数法针对成桥线形进行调索,表明该新型结构体系成桥线形及内力状态可通过调节拉索张拉力来调整。并通过简单模型分析,表明活载刚度对拉索初张拉力不敏感,满足线性分析原理,可单独进行活载分析。2、采用位移法对连续索张弦主梁矮塔斜拉桥结构在活载作用下的等效刚度方程进行推导,定性分析影响结构刚度的因素。公式表明,结构等效刚度与桥塔高度、撑杆长度、主跨跨度等几何参数及主梁刚度、拉索刚度等结构参数有关。通过借助传统斜拉索作临时支撑,定性模拟了施工过程,表明利用现有技术来建造连续索张弦主梁矮塔斜拉桥是可行的。3、对等效刚度方程给出的部分结构参数和几何参数进行详细的研究,以主梁活载刚度、结构内力、列车荷载下主梁动力反应等为指标进行对比分析,并与传统矮塔斜拉桥结构进行对比,表明连续索张弦主梁体系力学性能的优越性,同时给出合理的参数范围。4、考虑塔—梁—墩不同约束关系对结构性能的影响,分别建立塔墩固结梁支承体系和塔梁墩固结体系的模型,分析其在静力荷载、列车动力荷载、地震作用及温度作用下结构的力学反应,并与传统主梁体系作对比,以期对张弦主梁体系力学性能有更全面的认识。
[Abstract]:The cable-stayed bridge with low tower with continuous cable Zhang Xian girder is a kind of structural system which is based on the performance improvement of the cable-stayed bridge with low tower, and it also belongs to the expansion of the composite cable bracing system. It has the characteristics of small section of main beam, light weight of structure, large stiffness of live load and good dynamic performance, which makes it possible to apply it to high-speed railway bridges with strict rigidity requirements. The previous studies of the new structure system focus on highway bridges and lack of systematic analysis, but there is no systematic research on railway bridges. On the basis of previous studies, the structural arrangement of cable-stayed bridge with low tower with continuous cable Zhang Xian girder is carried out, and the stiffness and internal force of main beam under the action of high-speed railway are analyzed. The basic mechanical properties of the train under the action of the train are studied, and the parameters affecting the performance of the structure are analyzed, and the reasonable range of the parameters is summarized, which provides a reference for the engineering application. The main research contents and results are as follows: 1. The basic structure and cable-bar elements of the cable-stayed bridge with Zhang Xian main girder and low tower on high-speed railway are arranged. The unknown load coefficient method based on the influence matrix principle is used to adjust the cable shape of the bridge, which indicates that the state of the bridge shape and the internal force can be adjusted by adjusting the tension of the cable. Through simple model analysis, it is shown that the live load stiffness is not sensitive to the initial tension of the cable and satisfies the principle of linear analysis. The displacement method can be used to deduce the equivalent stiffness equation of the cable-stayed bridge with low tower and continuous cable Zhang Xian beam under the action of live load, and the factors affecting the stiffness of the structure can be qualitatively analyzed. The formula shows that the equivalent stiffness of the structure is related to the height of the bridge tower, the length of the brace, the span of the main span, the stiffness of the main beam and the stiffness of the cable. By using traditional stay cables as temporary support, the construction process is simulated qualitatively. It is shown that it is feasible to construct the cable-stayed bridge with low tower with continuous cable Zhang Xian beam by using the existing technology. The structural parameters and geometric parameters given by the equivalent stiffness equation are studied in detail, and the live load stiffness of the main beam and the internal force of the structure are studied in detail. The dynamic response of the main beam under train load is compared with that of the traditional cable-stayed bridge with low tower. The results show that the mechanical properties of the continuous cable Zhang Xian girder system are better than that of the traditional cable-stayed bridge. At the same time, the reasonable parameter range of .4 is given. Considering the influence of the different constraint relations between tower, beam and pier on the structure performance, the models of tower pier consolidation beam supporting system and tower beam pier consolidation system are established, and the static load and train dynamic load are analyzed. The mechanical response of the structure subjected to earthquake and temperature is compared with that of the traditional main beam system in order to have a more comprehensive understanding of the mechanical properties of the Zhang Xian main beam system.
【学位授予单位】：清华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.27

【相似文献】