跨铁转体施工斜拉桥抗震分析研究

Study on Seismic Analysis of Cable-stayed Bridge with Swivel Construction Across Railway

随着城市交通的快速发展,出现了大批跨越铁路的重要控制性桥梁。此类桥梁在施工中,需要保证不侵扰到桥下铁路线路的正常运营,因此,转体施工方法成为了此类桥梁的首选方法。转体施工的桥梁,其桥墩刚度较大。由于跨越铁路线路,多采用混凝土的上部结构,为避免钢结构后续的养护对线路运营的影响,因而上部结构较重。较重的上部结构和刚度较大的桥墩往往带来了抗震性能上的隐患。本文以转体施工的双塔混凝土主梁斜拉桥为例,对其进行反应谱、线性时程及非线性时程分析,以期为今后的转体施工跨铁路线路桥梁提供设计参考依据。

With the rapid development of urban traffic,a large number of important controllability bridges which across the railways have emerged.The bridges need to ensure that do not affect the normal operation of the railway lines under the bridge in construction.Therefore,the transfer construction method has become the first choice method of this kind of bridge.The stiffness of the bridge pier is large.Because of crossing the railway lines,that often use the superstructures of concrete to avoid the influence of the subsequent maintenance of steel structure on the operation of the lines,so the superstructure is heavy.The heavy superstructures and bridge piers with larger stiffness often bring the hidden trouble of seismic performance.This paper take the main girder cable stayed bridge of double tower concrete with swivel construction for example,making the analysis of response spectrum,linear time-history and nonlinear time-history,in order to provide reference for the design of bridges with swivel construction that cross railway lines.