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Severe changes in the profiles of the crossing nose are caused by large dynamic contact forces. To predict these forces as well as the profile evolution, the Whole System Model (WSM) was developed. However, it uses computationally expensive FE simulations. As a replacement, the semi-physical plasticity and wear model (SPPW) has been developed, thus majorly enhancing the overall performance of the WSM. The SPPW considers the influence of wear, plasticity, and wheel-profile-related effects. Its results have shown an overall good correlation with FE results, laboratory data for different materials, and field data from a real crossing. Due to the semi-physical nature of the model, the required computational time for the predictions was significantly reduced compared to FE simulations: minutes instead of weeks. The SPPW will be useful for time-efficient rail damage prediction, like wear and plastic deformation, and, as part of the WSM, contribute to a fast holistic track damage prognosis.

Detecting track geometry and rail surface defects using on-board vehicle monitoring systems is a key issue for rail infrastructure managers to increase availability and reliability while reducing the costs associated with monitoring and maintenance. Rail corrugation is one of the most common rail surface defects which grows in almost all metro, conventional and high-speed lines. This paper focuses on the development of a methodology to detect rail corrugation using axle box acceleration measurements acquired on an in-service high-speed vehicle. The main purpose of the proposed methodology is to distinguish the effect of rail corrugation on the accelerations from the other excitations that can be observed in the same wavelength range. For this purpose, the accelerations are analysed by calculating the fast Fourier transform and the spectrogram. Based on the characteristics of each excitation, the effects of modes of vibration, resonances, bridges, switches, and wheel defects are identified. From the remaining effects, which have congruent characteristics, a hypothesis of rail corrugation is formulated. The hypothesis is consolidated with multibody dynamics simulations and by comparing the corrugation indicators provided by the railway infrastructure company.