Analysis of rail structure interaction in continuous welded rails on railway bridges: a parametric analysis

Continuous welded rails (CWR) play a crucial role in modern high-speed rail networks due to their durability and stability. However, temperature-induced stresses significantly challenge rail and bridge integrity during train operations. This study investigates the complex interaction between rail and bridge properties, focusing on longitudinal stresses in CWR on railway bridges. Key parameters such as rail cross-sectional area, track stiffness, and bridge length are assessed for their impact on mitigating additional temperature stresses and moving loads in CWRs. Results demonstrate substantial stress reductions, particularly with track longitudinal resistance, followed by bridge expansion length and rail cross-sectional area. These findings provide valuable insights for enhancing railway safety and optimizing infrastructure design in the context of high-speed rail transportation. The analysis reveals that increasing the rail cross-sectional area effectively reduces temperature-induced stresses, with reductions of 13.23% for single-span bridges and 25% for double-span bridges. The construction of double-span bridges results in significant reductions in rail stress. Specifically, it leads to a decrease in tractive force stresses by 53.62–56.90% in tension and 53.35–54.39% in compression. Additionally, vertical load stresses are reduced by 61.35–58.70% in tension and 45.90–46.28% in compression.