Since railway is considered as optimal solution for the quickly growing transportation demand its design, construction and maintenance should get proper attention. In rail route design, we may need (be forced) to consider bridges and tunnels to pass obstacles (especially in countries like Ethiopia). And emphasis must be given for transition section like between bridges and embankments because when the railway route pass from embankment to bridge or vice versa the track bed stiffness (modulus)

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... ries causing abrupt change in vertical deflection which intern leads to frequent high vertical force exerted on the track structure, that cause more frequent damage to the track systems. So, this study gives emphasis to the damage on rail occurring at this transition section (specifically from embankment to bridge or vice versa). The study uses ABAQUS and FRANC 3D software to determine the stress that occurs on the rail at the transition section and the crack size (level of damage) respectively together with analytical equation to get some important parameters used for the analysis. Accordingly, the analysis results shows that due to the track bed stiffness difference the crack will be 3.5 mm at the rail base and 2.5 mm at the rail head. However, in depth experiments show that the rail can serve as long as the gap due to the crack is up to 70mm. Therefore, the probability of derailment happening is small. Even if the derailment happening probability is less, as cracks can propagate with increased number of cycles, the rail should be inspected and maintained frequently. From the numerical investigation, the inspection frequency of the rail at the transition section should be four times in a year (every three month). Finally, the conclusions of the research are presented with recommendations for further research by adding other factors that affect stiffness at transition sections.