基于行波效应的特大跨拱桥地震易损性分析

发布时间：2018-03-20 16:27

本文选题：钢筋混凝土拱桥　切入点：行波效应　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着世界各国跨江跨海工程、连岛工程的不断建设，桥梁工程正朝跨度更大、受力更合理、造价更节约的方向发展。钢筋混凝土拱桥以其优越的跨越能力、简洁的传力机制、经济的工程造价、较低的维护费用深受桥梁工程师的青睐。重庆万州长江大桥以420m的跨径成为当今世界上跨度最大的钢筋混凝土拱桥，欧洲、日本、克罗地亚等国家先后开展了600~1000m级特大跨度混凝土拱桥可行性研究，并取得了一定的研究成果。本文以日本土木协会于1999年着手试设计的一座600m跨的特大跨钢筋混凝土拱桥为研究对象，通过以下几项工作对桥梁的地震响应特点和易损性性能进行了研究： ①建立结构的弹性分析模型，探究拱桥自身的动力特性，并选取8条典型的地震波进行不同步输入，提取结构控制点的响应参数，分析地震频谱特性和峰值加速度对行波效应影响产生的作用，并认为行波效应对拱桥地震响应的影响不可忽略。 ②在弹性分析模型上建立非线性分析模型，运用IDA法开展行波效应的时程输入，提取地震响应的有关参数，包括控制节点位移、控制节点加速度、控制截面内力和控制截面变形，获取各参数随地震强度的变化规律，并初步判断拱桥的拱脚位置、1/4跨位置和3/4跨位置应作为地震作用下特大跨钢筋混凝土拱桥易损性分析的主要对象。 ③最后，利用能力需求法分析结构抗震性能的原理，将拱桥截面的弯矩-轴力时程曲线和弯矩-轴力相关曲线进行对比，探寻拱脚截面地震内力响应随地震强度增大产生的变化规律。通过分析拱脚截面的内力能力需求比，得到拱脚是该类桥梁的地震作用下的薄弱位置，且后激励拱脚较先激励拱脚更容易发生破坏，，其内力能力需求比仅为后者的1/3~1/2。
[Abstract]:With the continuous construction of river and sea crossing projects and even island projects in various countries in the world, bridge engineering is developing towards the direction of larger span, more reasonable force and more economical cost. Reinforced concrete arch bridge is developing with its superior leapfrogging ability and simple force transfer mechanism. Economic engineering cost and low maintenance cost are favored by bridge engineers. Chongqing Wanzhou Yangtze River Bridge with a span of 420 meters has become the world's largest span reinforced concrete arch bridge, Europe, Japan, Croatia and other countries have carried out the feasibility study of 600-1000m large span concrete arch bridge, and obtained certain research results. In this paper, a 600m span reinforced concrete arch bridge with a span of 600m was designed in 1999. The characteristics of seismic response and vulnerability of the bridge were studied through the following work:. The main contents are as follows: 1. The elastic analysis model of the structure is established, and the dynamic characteristics of the arch bridge itself are explored. Eight typical seismic waves are selected for asynchronous input, and the response parameters of the control points of the structure are extracted. The effect of seismic spectrum and peak acceleration on the traveling wave effect is analyzed, and it is considered that the influence of traveling wave effect on the seismic response of arch bridge can not be ignored. (2) the nonlinear analysis model is established on the elastic analysis model. The IDA method is used to carry out the time-history input of the traveling wave effect, and the relevant parameters of the seismic response are extracted, including the control of the node displacement and the control of the node acceleration. The internal force of the section and the deformation of the section are controlled, and the variation of the parameters with the earthquake intensity is obtained. The arch foot position and 3/4 span position of arch bridge should be regarded as the main objects of vulnerability analysis of large span reinforced concrete arch bridge under earthquake. Finally, the moment axial force time-history curve and the moment axial force correlation curve of the arch bridge section are compared by using the principle of capacity demand method to analyze the seismic performance of the structure. By analyzing the internal force demand ratio of arch foot section, it is found that arch foot is the weak position of this kind of bridge under earthquake action. The post-excitation arch is more likely to destroy than the first, and its internal force demand ratio is only 1 / 3 / 1 / 2 of the latter.
【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】：U448.22;U442.55

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