地震作用下高速铁路FPS隔震桥梁无砟轨道力学特性参数研究

为了准确分析地震作用下高速铁路FPS隔震桥梁无砟轨道的纵向力学特性,以一典型5跨FPS隔震简支梁桥为对象,建立基于CRTSⅡ型板式无砟轨道的线桥一体化模型;应用非线性时程方法分析无砟轨道的纵向力学特性并进行参数研究。研究结果表明:地震作用下,梁端的轨道纵向力要大于梁中间位置;滑动层与剪力齿槽的设计能减小底座板与梁面的纵向相互作用,且道床板纵连能分散从梁面传来的纵向力,使CA砂浆及扣件的纵向力降低;FPS摩擦系数、支座半径、滑动层摩擦系数、剪力齿槽刚度对轨道纵向力有较大影响,在高速铁路FPS隔震设计时,应综合考虑各参数对Ⅱ型板纵向地震受力的影响,在保证正常运营的同时,减小Ⅱ型板纵向地震受力,防止轨道发生纵向破坏。

Parametric Study of Mechanical Performances of Ballastless Track on High-speed Railway Bridge Isolated with FPS during Earthquake

To analyze accurately longitudinal dynamics performances of the ballastless track on highspeed railway bridge isolated with FPS during earthquake, an integrated model for CRTS Ⅱ slab ballastless track is established based on a typical simply supported girder bridge( SSGB); The model is used to analyze the longitudinal mechanical performances of ballastless track and investigate the influence of parameters with nonlinear time-history analysis method. The results show that the longitudinal forces of the track at the end of beam is greater than the track at the middle of the beam during earthquake; the design of sliding layer and shear alveolar may reduce the longitudinal interaction between beam and track,longitudinal connected track may disperse the longitudinal forces from the beam to reduce the longitudinal forces of CA mortar and fastenings; Such factors as frictional coefficient and radius of FPS,frictional coefficient of sliding layer,stiffness of shear alveolar impose great effect on longitudinal forces of track. In order to prevent damage of track,the effect of parameters should be comprehensively considered to minimize longitudinal forces of track while normal operation of high-speed railway is guaranteed.