城轨U梁与箱梁桥上无缝线路受力及桥梁固有振动特性分析

Analysis of the Forces of CWR on Bridge and Natural Vibration Characteristic of U-beam Bridge and Box-girder Bridge of Urban Railway

针对城市轨道交通中新型U梁及传统型式箱梁两种不同型式桥梁,分别从线路纵向阻力及桥墩水平刚度等方面,对桥上无缝线路钢轨受力、桥墩受力、桥梁挠度及两种桥梁固有振动特性等方面进行对比研究.研究结果表明:与箱形梁相比,U型梁的钢轨挠曲力较小,而桥墩受力较大.U型梁固有振动频率比箱型梁小,且U型梁的2阶横向振动出现较早.该结果为城市轨道交通设计提供理论参考依据.

Aimed at two types of urban rail transit system bridges,one is the U-beam bridge—the new type and the other is the box-girder bridge—the traditional type,this paper makes a detailed analysis on the rail force,the pier force,bridge deflection and the natural vibration characteristics of two types.And the comparative analysis is applied to the U-beam bridge and the box-girder bridge.The results show that the rail additional flexural force of U-beam is smaller than the box-girder beam,but the pier force of U-beam is larger.The natural vibration frequency of U-beam is smaller than box-girder beam.And the 2nd transverse vibration of U-beam occurs earlier.These results can provide a theoretical basis for the design of urban rail transit.