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In this paper, the main factors in the analysis of the railway concrete sleepers areinvestigated and new recommendations are made in order to improve the accuracy of the currentpractices in analysis of the railway track system. First, a comprehensive literature survey isconducted, then, FEM models for a railway track system are developed and used to discuss andevaluate the assumptions commonly used in the analysis of the railway track system. The analysisfactors investigated include stress distribution under a concrete sleeper, rail-seat load, anddynamic coefficient factor. Finally, recommendations and needs for continuation of the researchare presented.

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The track stiffness experienced by a train will vary along the track. Sometimes the stiffness variation may be

very large within a short distance. One example is when an unsupported sleeper is hanging in the rail. Track stiffness

is then, locally at that sleeper, very low. At insulated joints the bending stiffness of the rail has a discontinuity implying

a discontinuity also of the track stiffness. A third example of an abrupt change of track stiffness is the transition from

an embankment to a bridge. At switches both mass and stiffness change rapidly. The variations of track stiffness will

induce variations in the wheel/rail contact force. This will intensify track degradation such as increased wear, fatigue,

track settlement due to permanent deformation of the ballast and the substructure, and so on. As soon as the track

geometry starts to deteriorate, the variations of the wheel/rail interaction forces will increase, and the track

deterioration rate increases. In the work reported here the possibility to smooth out track stiffness variations is

discussed. It is demonstrated that by modifying the stiffness variations along the track, for example by use of grouting

or under-sleeper pads, the variations of the wheel/rail contact force may be considerably reduced.