大跨度钢—砼组合拱桥地震反应分析

发布时间：2018-03-25 22:09

本文选题：地震　切入点：大跨径钢混组合拱桥　出处：《重庆交通大学》2014年硕士论文

【摘要】：钢-混组合结构已经在大跨度斜拉桥、拱桥、连续刚构桥中得到广泛应用,取得了良好的力学效果。随着拱桥跨度的增大,拱圈自重显著增加,这已成为制约拱桥朝更大跨度发展的重要因素。为此,本文以重庆万州长江大桥420m拱桥为原型,探索性地提出了拱脚区段为混凝土拱箱、拱顶区段为钢箱的一种新型大跨钢-混组合拱桥,达到减轻自重的目的。由于拱圈由两种不同材料组成,截面刚度存在较大差异,因此有必要开展结构动力特性、抗震性能及其钢-混分界点位置影响研究： ①采用大型有限元分析软件SAP2000进行结构动力特性计算,分析钢-混组合拱桥的动力特性,探讨前500阶振型对结构抗震性能的影响程度。 ②由于主拱圈由钢和混凝土两种不同材料构成,采用试算方法讨论分界点位置对结构模态的影响。 ③选用EL-Centro地震波以及Taft地震波进行结构非线性时程分析,研究单个方向激励以及多个方向耦合激励对钢-混组合拱桥非线性时程分析的适用性。基于非线性时程分析计算结果,讨论钢和混凝土在拱圈上的分界点问题。 ④将EL-Centro和Taft地震波以位移波的形式输入,通过在两个拱脚间设置多种时间相位差,从位移和内力两个方面探讨行波效应对钢-混组合拱桥的影响规律。 ⑤针对分析结果,指出钢-混组合拱桥的抗震薄弱环节,提出几种初步改进措施,并从桥梁抗震角度展望这种新型钢混组合拱桥在实际工程中的应用前景。
[Abstract]:Steel-concrete composite structures have been widely used in long-span cable-stayed bridges, arch bridges and continuous rigid frame bridges. This has become an important factor restricting the arch bridge to the development of a larger span. Therefore, this paper takes the 420m arch bridge of Wanzhou Yangtze River Bridge in Chongqing as the prototype, and puts forward that the arch foot section is concrete arch box. The section of arch roof is a new type of large-span steel-hybrid composite arch bridge with steel box, which can reduce the deadweight. Because the arch ring is composed of two different materials and the section stiffness is quite different, it is necessary to develop the dynamic characteristics of the structure. Study on Seismic performance and location of Steel-concrete Boundary Point:. The main contents are as follows: 1. The dynamic characteristics of steel-concrete composite arch bridge are calculated by using the large-scale finite element analysis software SAP2000, and the influence of the first 500th vibration modes on the seismic behavior of the structure is discussed. (2) because the main arch ring is composed of two different materials, steel and concrete, the influence of the location of the boundary point on the structural mode is discussed by the method of trial calculation. (3) EL-Centro and Taft seismic waves are used for nonlinear time-history analysis of structures. The applicability of single directional excitation and multi-directional coupled excitation to nonlinear time-history analysis of steel-concrete composite arch bridge is studied. The results of nonlinear time-history analysis are based on the results of nonlinear time-history analysis. The boundary point of steel and concrete on arch ring is discussed. (4) the EL-Centro and Taft seismic waves are input in the form of displacement waves. By setting a variety of time phase differences between the two arches, the influence of traveling wave effect on steel-concrete composite arch bridge is discussed from two aspects of displacement and internal force. 5. In view of the analysis results, the paper points out the weak link of the steel-concrete composite arch bridge, puts forward some preliminary improvement measures, and looks forward to the application prospect of the new steel-concrete composite arch bridge in the practical engineering from the angle of the bridge seismic resistance.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U442.55;U448.22

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