Evaluating the non-linear static and dynamic stiffness of rail pad using finite element method / Mohamad Hazman Halim

In the realm of railway infrastructure, the significance of rail pads cannot be overstated, particularly in their role in mitigating noise and vibration generated by trains. This study employs the finite element method (FEM) to conduct a thorough analysis of the nonlinear static and dynamic stiffness of rail pads, considering various loading conditions such as temperature, toe-load, and frequency. The investigation reveals a crucial dependency of dynamic stiffness on loading frequency, with higher frequencies resulting in a reduction of stiffness. The nonlinear static stiffness is significantly influenced by temperature and toe-load variations. These findings contribute valuable insights into the behaviour of rail pads under diverse conditions, offering a foundation for optimizing their design to enhance performance in railway applications. Addressing existing research gaps, this study sheds light on the limited exploration of temperature's impact on rail pads' static and dynamic behaviour, emphasizing aspects of deformation and stiffness. Furthermore, the investigation delves into the less-explored territory of varying toe loads, examining their effects on rail pads' static and dynamic responses, particularly in the context of wear and fatigue. Additionally, the influence of frequency on dynamic responses, particularly concerning train speeds and track irregularities, is a focus of this study. To achieve these objectives, a 3D FE model based on hyperelastic formulation for non-linear rail pad materials is developed. The research aims to estimate static and dynamic stiffness under diverse loading conditions and investigate the effects of parametric changes on rail pad stiffness. In conclusion, the findings of this study provide a comprehensive understanding of rail pad behaviour under different conditions, emphasizing the critical factors of temperature, toe load, and frequency. The outcomes contribute to informed decision-making in the design and maintenance of railway infrastructure, ultimately optimizing rail systems for enhanced performance and durability.