采用非线性弹簧单元模拟道床的纵向位移阻力关系,建立了地震作用下桥梁与轨道共同作用的线桥一体化模型,分析轨道约束对铁路桥梁纵向抗震性能的影响。研究表明,在地震中当桥墩刚度相近时,轨道约束对桥墩是有利的;当桥墩刚度相差较大时,轨道约束对刚度较大桥墩有时是不利的。文章还分析了道床阻力、桥梁跨数等因素对桥梁抗震的影响。 The non-linear spring element is used to simulate the longitudinal displacement resistance of ballast bed. An integrated model of bridge-track interaction under earthquake action is established, and the influence of orbital constraints on longitudinal seismic behavior of railway bridges is analyzed. The research shows that when the stiffness of bridge piers is similar, the orbital constraint is beneficial to the piers. When the stiffness of the piers is quite different, the orbital constraint is sometimes unfavorable for larger piers. The article also analyzes the impact of the factors such as the resistance of the bed bed and the span of the bridge on the seismic resistance of the bridge.