铁路梁式桥支座破坏对下部结构地震反应的影响

发布时间：2019-07-08 17:54

【摘要】：在近年来历次地震中,铁路桥梁破坏严重,其中支座破坏是桥梁破坏的主要形式之一。因此,有必要深入研究支座的不同传力方式,分析支座破坏状态对桥墩地震反应的影响。本文针对球型钢支座,以某高速铁路桥梁为研究对象,建立轨道系统为CRTSⅡ板式无砟轨道的线桥一体化计算模型,并与不考虑轨道刚度影响的传统计算模型进行对比分析,研究罕遇地震下支座破坏对桥墩地震反应的影响。本文主要工作如下:(1)收集整理了支座的不同工作状态对桥梁的地震反应影响的研究文献,介绍了支座震害特点和国内外支座破坏的研究现状,总结了CRTSⅡ板式无砟轨道线桥一体化模型在不同设防等级下的建模方法。(2)以十跨简支梁桥及连续梁桥作为研究对象,采用SAP2000软件建立不考虑轨道约束的传统计算模型和考虑轨道约束的线桥一体化模型,进行了动力特性分析。结果表明,轨道约束对高速铁路桥梁的动力特性影响较大。(3)选取铁路桥梁中广泛使用的球型钢支座,基于传统计算模型,分析了支座的受力特点以及支座破坏对桥墩地震反应的影响。结果表明,在地震作用下,对于墩高相近的简支梁桥,同一桥墩的两排支座同时进入干摩擦状态之后,该墩地震反应明显降低;对于连续梁桥,固定支座进入干摩擦状态之后,固定墩地震反应明显降低。(4)基于线桥一体化抗震模型,分析了罕遇地震下支座破坏对桥墩地震反应的影响。结果表明,轨道约束对简支梁桥支座破坏后桥墩的地震反应有削弱作用,而对连续梁桥各墩地震反应有放大作用。
文内图片：

图片说明：码头大桥支座破坏
[Abstract]:In recent years, railway bridges have been damaged seriously, among which bearing failure is one of the main forms of bridge failure. Therefore, it is necessary to study the different force transfer modes of the bearing and analyze the influence of the failure state of the bearing on the seismic response of the pier. In this paper, aiming at the spherical steel bearing, taking a high-speed railway bridge as the research object, the integrated calculation model of the track system as CRTS II slab ballastless track is established, and compared with the traditional calculation model without considering the influence of track stiffness, the influence of bearing failure on the seismic response of bridge pier under rare earthquake is studied. The main work of this paper is as follows: (1) the research literature on the influence of different working states of supports on the seismic response of bridges is collected and sorted out, the characteristics of bearing earthquake damage and the research status of bearing failure at home and abroad are introduced, and the modeling methods of CRTS II slab ballastless track bridge integration model under different fortification grades are summarized. (2) Ten-span simply supported beam bridges and continuous beam bridges are taken as the research objects. The traditional calculation model without considering track constraint and the integrated model of line and bridge considering track constraint are established by using SAP2000 software, and the dynamic characteristics are analyzed. The results show that the track constraint has a great influence on the dynamic characteristics of high-speed railway bridges. (3) based on the traditional calculation model, the bearing characteristics and the influence of bearing failure on the seismic response of high-speed railway bridges are analyzed. (3) the spherical steel bearings widely used in railway bridges are selected, and based on the traditional calculation model, the bearing characteristics and the influence of bearing failure on seismic response of piers are analyzed. The results show that under the action of earthquake, for the simply supported beam bridge with similar pier height, the seismic response of the pier decreases obviously after the two rows of supports of the same pier enter the dry friction state at the same time; for the continuous beam bridge, the seismic response of the fixed pier decreases obviously after the fixed support enters the dry friction state. (4) based on the integrated seismic model of the line bridge, the influence of bearing failure on the seismic response of the pier under rare earthquake is analyzed. The results show that the track constraint can weaken the seismic response of the pier after the support failure of the simply supported beam bridge, but amplify the seismic response of each pier of the continuous beam bridge.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U442.55

【参考文献】