多点地震输入对桥梁动力反应的影响分析

发布时间：2018-01-06 15:27

本文关键词：多点地震输入对桥梁动力反应的影响分析　出处：《华北理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：大跨桥梁结构是我国交通运输生命线上的一项不可分割的重要组成部分。目前在桥梁结构抗震领域的研究,以及探索找到更加有效的方法来抵抗地震作用下对桥梁结构的破坏一直是众多学者们研究追求的核心目标。大跨度桥梁结构经常是车辆行驶比较密集的交通公共场所,其抗震安全性能不能轻易的忽视。而对于大跨桥梁结构本身所具有的跨度比较大的这个特点使得其在桥梁抗震领域计算方法的研究比普通的其他结构要复杂的多,所需要考虑进去的因素也会更多。对于大跨结构地震动力响应分析大多数传统的分析方法就是忽视地震动在空间范围内的变化,即认为结构的各个支撑点处地震时地球表面运动都是相同的。然而相对于一些跨度比较大的桥梁结构,其桥梁结构延伸较长,不同桥墩支座处的高度差也比较大,应用一致地震输入方式所得到的数据结果也不符合真实的情况。所以,推究大跨桥梁非一致地震输入响应,拥有非常重大的理论意义和工程研究价值。根据拉格朗日方程推求了多点地震动输入时对三跨简支梁桥的地震动力反应计算公式,并编制了龙格-库塔法数值求解程序。通过比较同一个桥梁模型分别在三条地震波作用下的动力反应结果可以得出同一个结论,对于大跨度桥梁结构考虑多点地震动输入的情况下,纵梁-桥墩的相对位移明显比一致地震输入下有所增加,当时间间隔为0.1s时,位移增大系数可达4.96倍。纵梁质量、桥墩截面刚度及等效阻尼值对墩梁的相对位移影响较大。在大跨度桥梁结构设计时,有必要综合考虑三者的影响,选择最优组合,避免发生落梁破坏。
[Abstract]:Large span bridges is an integral and important part of transportation lifeline in China. The current research in the field of bridge structure seismic exploration, and find a more effective method to resist the earthquake damage to the bridge structure has been many scholars research the core goal. The long-span bridge structure is often the vehicle traffic public places more intensive, the seismic safety performance can not be easily ignored. And the characteristics of the long-span bridge structure itself has a relatively large span in the bridge seismic field calculation method of the research is much more complicated than other ordinary structure, need into account also more. For large span structure seismic response analysis of most of the traditional methods is to ignore the seismic changes in the spatial scope, that the structure of each The earthquake at the supporting point movement of the earth's surface are the same. However, compared with some relatively large span bridge structure, the bridge structure extends longer, the height difference of different pier bearing in the application of uniform seismic input results from the do not accord with the real situation. So, to bridge the non input response consistent earthquake, has theoretical significance and value engineering research is very important. According to the calculation formula of seismic dynamic response of three span beam bridge Lagrange equation for multi point seismic input, and the Runge Kutta numerical solution procedure. By comparing with a model of bridge dynamic response results respectively in effect under three seismic waves can come to the same conclusion, for the long-span bridge structure considering ground motion input, the relative displacement of beam pier is more obvious than Uniform seismic input increased, when the time interval is 0.1s, displacement coefficient of up to 4.96 times. The longitudinal quality of pier stiffness and the damping value of relative displacement of pier and girder has great influence. In the design of long-span bridges, it is necessary to consider the influence of the three, to select the optimal combination, avoid drop beam damage.

【学位授予单位】：华北理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U442.55

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