Parametric Study on Railway Fastening System Response Subjected to Different Axle Load

are several factors causing fastening systems to deteriorate faster than the designed life. The high repetitive loads from a moving train being one of the main factors, track irregularities, design and installation defects of track components, non-uniform rail support stiffness, are some of the factors causing fastenings systems to deteriorate faster than the theoretical design life span. The non-uniform support structure induces higher dynamic forces into the track system, leading to early failure of the fastening system. The dynamic forces from the wheel-rail contact transfer to the track subgrade through the fastening system. The fastening acts as a damping to the track system but itself experiences high magnitude undamped dynamic forces. The mechanical properties of the fastening system are the most important characteristics that directly determine the long-term performance of this component. A finite element analysis was carried out to analyze the influence of mechanical properties and geometries of the fastening system on its deterioration. The analysis is done to determine the response of the fastening system under different loading scenarios by changing the mechanical properties. The parameters include: density, young’s modulus, yield strength and ultimate strength. A finite element model of a track system built is composed of standard rail (UIC60), rail pad, abrasion plate, rail clip, bolt, insulator and half sleeper, all modeled as solid elements. The model is developed and analyzed using finite element package ANSYS software. The result shows that the mechanical properties and thickness have a great effect on the fastening system components’ deterioration. It has been shown that the density has the littlest effect among other parameters and, on the other hand, the young’s modulus has seen to have a great effect among the parameters. Finally, the properties of a conceptual rail-fastening system for heavy hauls have been identified. The results presented in this study add more knowledge of mechanistic design theory for fastening systems.