Stress–free temperature variation and buckling potential in railway tracks: Dynamic finite element modelling and implications

Climate change amplifies temperature fluctuations and extreme weather events, potentially increasing the risk of buckling in continuously welded rail track. Current mitigation strategies, such as imposing conservative speed restrictions during hot weather, are mainly reactive and may be costly and disruptive. This Paper investigates the variation of stress-free temperature and its influence on buckling potential along railway track, by means of dynamic finite element analysis. A 3D Abaqus model, which accounts for permanent deformation of the sleeper positions and rail geometry, is developed to simulate the dynamic response of a track subjected to temperature cycles. A parametric study investigates the effects of key factors: rail lateral misalignment, longitudinal temperature gradient, fastening system strength, train speed, braking force and track curvature. The results give insights into the potential range of axial stress profiles, residual displacements and stress-free temperature variations along continuously welded railway track. Vulnerable track sections, such as those exposed to differential heating and cooling, unidirectional braking/acceleration, and with degraded fasteners, are identified. The findings can be used to support the development of more effective and proactive maintenance strategies, inform revisions to current standards, and help reduce operational disruptions. Additionally, the methodology provides a transferable framework for international rail operators facing similar climate change-induced risks.