Analysis of the Effect of Temperature Variations Around Tunnel Ventilation Shafts on Continuous Welded Rail Fractures

This study examines factors affecting the thermal expansion behavior of continuous welded rails (CWRs) in urban rail systems and investigates conditions that lead to rail weld fractures. Parameters affecting CWR fractures near ventilation shafts in urban rail systems are identified through field investigations and machine learning analysis. Further, a computational fluid dynamics analysis is employed to evaluate the range of temperature variation around tunnel ventilation shafts that affects the CWR fractures. Load conditions that incorporate temperature variations are applied using a validated numerical model to analyze changes in the axial force on the CWRs. The results confirm that increased localized temperature fluctuations around tunnel ventilation shafts lead to a higher frequency of CWR fractures.