Effects of vertical stiffness of rail fastening system on the behavior of the end regions of railway bridges with slab tracks

A railway bridge with slab track is subjected to end rotations because of the deflection of the girder during train operation. At the ends of a slab track, the end rotation of the bridge girder causes uplift deformation of the slab track, and leads to compressive stresses in the rail fasteners. In this study, a prototype bridge consisting of one span of a girder and one span of an abutment along with a slab track was constructed, and the uplift and compressive forces generated in the rail fastening system were experimentally analyzed. To effectively analyze the experimental results using a numerical method, a series of finite element analyses were performed considering the nonlinear nature of the rail fastening system. A comparison between the experimental and analytical results indicated that the higher the stiffness of the rail fastening system, the greater the uplift and compressive forces. In addition, a nonlinear model provided better correlation with the experimental results than a linear model. Therefore, when reviewing the serviceability of the rail fastening system at railway bridge ends, an adequate finite element model considering the uplift and compressive forces in the rail fastening system should be used.