中文摘要：

研究目的：基于有限元方法与梁轨相互作用原理，建立能够分析坡道上无砟轨道桥梁变形对扣件受力影响的平面模型，分析桥梁坡度、墩顶纵向水平位移等因素对扣件受力的影响，提出在考虑桥梁收缩徐变、基础沉降、桥墩纵向温差及列车荷载等条件下32m简支梁适应的坡度，从而为桥梁坡度选择提供理论指导。研究结论：（1）桥梁坡度以及墩顶纵向水平位移的改变均会引起扣件受力，并且扣件所受上拔力最大值随着桥梁坡度、墩顶纵向水平位移的增加近似呈线性增大；（2）对于梁端悬出0．55m的32m简支梁而言，当桥墩高度为20m时，由扣件上拔力不超限确定的最大坡度值为29‰，当桥墩高度为40m时最大坡度值为20‰；（3）当桥墩纵向水平刚度增加、梁缝附近铺设过渡板或采用特殊扣件时，可以适当增加桥梁的坡度限值；（4）基于扣件受力确定的桥梁坡度限值可为今后线路选线设计及桥梁坡度设置提供借鉴和参考。

英文摘要：

Research purposes： A plane model which could analyze the influence of bridge deformation on fastener force was established based on the finite element method and the track - bridge interaction theory. The influence of bridge gradient and longitudinal displacement of pier top on fastener force was analyzed. The adaptive gradient for 32 m simply- supported beam bridge under the load of bridge shrinkage creep, the foundation settlement, temperature difference between one side and another side of pier, train and so on was put forward to provide theoretical guidance for the selection of gradient of bridge. Research conclusions： （ 1 ） The change of bridge gradient and longitudinal displacement of pier top can cause fastener force and the maximum of uplift force increases approximately linearly with the increment of bridge gradient and longitudinal displacement of pier top. （2） For the 32 simply -supported beam bridge whose distance between beam end and adjacent bearing is 0.55 m, when the height of pier is 20m, the maximum gradient is 29‰ to ensure the uplift force of fastener within the limit, while when the height is 40m, the gradient is 20‰. （ 3 ） When increasing longitudinal horizontal stiffness of pier or using transition slab or special fastener system between the ends of two beams, the maximum gradient can be appropriately raised. （4） The maximum gradient of bridge ascertained by the uplift force offasteners can provide the reference for the railway loaction design and the setup of bridge gradient in future.