Keywords: ballast track, continuous welded rail, switches & crossings, rail stress, simulation, FEM.

Continuous Welded Rail (CWR) tracks develop significant axial forces when subjected to temperature variations, and these forces can be amplified in the vicinity of switches due to their geometric discontinuities and heterogeneous support conditions. This paper presents an extended nonlinear finite element study aimed at quantifying thermal stress amplification in switches integrated into CWR zones. The model incorporates the full three?dimensional geometry of the switch, including the transition from common to separate sleepers, the detailed crossing region, and nonlinear longitudinal and lateral ballast resistances. A comprehensive simulation campaign is carried out to evaluate the combined influence of three key parameters: the switch angle, which determines the sleeper topology, the rail profile, and the sleeper type (timber or concrete), which affects the mobilised ballast resistance. For each configuration, the model computes the maximum axial stress induced during a temperature rise, relative to an equivalent straight CWR track. The results are synthesised into an engineering abacus that provides the peak axial stress as a function of temperature variation for any combination of switch angle, rail profile, and sleeper type. This abacus is intended to support railway engineers in assessing buckling risk, planning maintenance operations, and optimising neutral temperature management in switches installed on CWR tracks. The study demonstrates that switch angle, rail stiffness, and sleeper material all exert a significant influence on thermal stress amplification, and that their combined effect must be accounted for in engineering assessments.

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