市域铁路无砟轨道梁端转角限值研究

Research on the Limit Value of Angles of Rotation at Bridge End of City Railway Ballastless Track

无砟轨道与桥梁处于很大的刚性连接状态,梁端微小的转动将会对轨道结构产生较大的影响。以温州市域铁路为例,建立了铺设无砟轨道的35 m简支梁桥梁端转角计算模型,并以扣件最大上拔力作为限值指标,研究了不同梁端悬臂长度下的合理梁端转角限值。研究表明:(1)梁端单侧向下转动方式下扣件系统受力最为不利,是控制梁端转角限值的主要转动方式;(2)梁端向上和向下转动时各扣件受力方向相反,梁缝处扣件承受最大上拔力或压力;(3)梁端悬臂长度越长,扣件受力越不利。

The ballastless track and the bridge are in a very rigid connection state,and the slight rotation of the beam end will have a greater impact on the track structure.In this paper,taking W enzhou city railway as an example,a calculation model of angle of rotation at bridge end of a 35 m simply-supported beam bridge with ballastless track is established,and the maximum pressure of fastener is used as the limit index.The reasonable beam end rotation angle under different overhanging lengths of bridge end are studied.The research shows that:(1)the fastener system suffers the most unfavorable force under the single angle of rotation at bridge end,and it is the main rotation method for controlling the limit value of the angle of beam end;(2)the force of fasteners is in opposite directions when the beam end is turned up and down,and the fasteners at the beam end are subjected to the maximum pull or pressure force;(3)the longer the overhanging lengths of bridge end,the more disadvantageous of the fastener is at the beam end.