As essential track components for rail connections and signal transmission and control, insulated rail joints (IRJs) have been widely used in traditional and high-speed railways. However, the IRJ is considered as one of the weakest parts of railway track structures due to the significant discontinuities in stiffness and geometry. When a train runs over an IRJ, a wheel-rail impact occurs and it increases with train speed. The impact consequently leads to vibration and noise and accelerates track deterioration in the vicinity of the IRJ. This paper establishes an explicit finite element wheel-IRJ dynamic interaction model to simulate highfrequency impact vibration and noise generated at a typical IRJ in the Dutch railway network, and validates the model against a comprehensive hammer test and a pass-by measurement. Good agreements between the simulation and measurements indicate that the proposed model can effectively reproduce high-frequency impact vibration and noise up to 10 kHz. This paper also connects the dominant frequencies of wheel-IRJ impact vibration and noise with the dynamic behaviour of the target IRJ, which may contribute to the mitigation of impact vibration and noise at IRJs as well as to train-borne detection of deterioration types of IRJs.

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Vibration-based condition monitoring is a powerful tool for remotely assessing the quality of railway components. Due to its design, railway crossings suffer from faster degradation, because of the transition from stock rail onto the needle. Since this is also a repetitive load, a small amount of wear will increase the degradation. Measuring the dynamic response also contains information about the transition of the train wheel from the stock rail onto the needle. In this paper, a setup that measures the acceleration and the strain of a railway crossing during train passages is presented. The responses of these two measurement techniques are analyzed for two different types of trains. A linear correlation between the peak values of the strain and the nominal axle load is presented with a regression value of − − 1.8•10 5. From the accelerations, both the displacement and the transient wheel-rail contact can be analyzed.

This paper describes an approach for characterizing the dynamic behavior of the vehicle/track interaction at railway crossings. In the approach, we integrate in situ axle box acceleration (ABA) measurements with roving-accelerometer hammer tests to evaluate the influence of train speed, train moving direction (facing and trailing directions), sensor position (leading and rear wheels of a bogie), and the natural response of track structure on ABA signals. The analysis of data from multiple sensors contributes to the following findings: the major frequency bands of the vertical ABA are related to the natural frequencies of the crossing; thus, these ABA frequency bands are not greatly affected by variations in train speed, moving direction, and sensor position. The vibration energy concentrated at the major ABA frequency bands increases at higher train speeds, along the facing moving direction and from the leading wheel. The crossing rails vibrate as a combination of bending and torsion rather than solely bending at the major ABA frequency bands, since the vibrations of the wing rails are not synchronized. These results help enhance our understanding of the vehicle/track interaction at crossings and can be used to improve the dynamic response-based system for monitoring the condition of crossings.

In this paper, we present a method for evaluating the performance of railway crossing rails after long-term service. The method includes 1) 3D profile and hardness measurements; 2) finite element simulation of wheel/ rail interaction; and 3) numerical prediction of rail degradation. We conducted a case study on a crossing that had been in service for several years. The results indicate that the crossing experienced a run-in process in the major traffic direction, manifested as a widening of the running band, an enlargement of the contact patch size, a decrease in contact stress and eventually a reduction in plastic deformation and wear. However, the wheel/rail interaction was exacerbated in the minor traffic direction which induced more severe plastic deformation and wear.