Dynamic Linear Analysis of a Resilient Slab-Track Structure for High-Speed Railway System: Evaluation of the Dynamic Magnification Factor

This paper presents a dynamic non-linear analysis of a resilient slab- track structure designed for high-speed railway systems. The slab-track structures comprise sandwich-type configurations with internal self-compacting concrete (SCC) layers, ensuring enhanced resilience. A novel approach utilizing two- dimensional frame elements and two-joint links is employed to connect the layers of the slab-track structure. The study conducts independent evaluations of both the lateral and longitudinal directions of the slab track, subjecting them to a series of time-history load functions that accurately represent the dynamic forces exerted by wheel trains operating at various speeds and ideal subgrade conditions. The time-history load functions consider factors such as the size and pitch spacing of the wheel, directly influencing the intensity of the applied loads. The ideal subgrade condition is set to mimic a rigid pavement with a California Bearing Ratio (CBR) equivalent to eight percent to establish a benchmark. The primary focus of the investigation centers around the Dynamic Magnification Factor (DMF), which is determined by comparing the dynamic and static internal forces, such as bending moment and shear force. The research findings reveal a significant correlation between the DMF and train velocity. As the train speed increases from 50 to 200 km/h, in most cases, the DMF values exhibit an escalating trend. This analysis provides valuable insights into the behavior of the resilient slab-track structure under varying high-speed conditions, offering essential information for the design and optimization of future high-speed railway systems.