An approach to evaluate wheel-rail match properties considering the flexibility of ballastless track: Comparison of rigid and flexible track models in wheel-rail profile matching

摘要

Many different wheel/rail profiles are used in the China high-speed railway, and vehicle operation safety and comfort will decrease if the inappropriatewheel-rail profile pair is used. To solve the problem of estimating the wheel-rail match, many numerical models, including vehicle system dynamic modelsand wheel-rail rolling contact models, have been established to analyse the wheel-rail dynamic responses. Both methods have less consideration of theflexibility and vibration characteristics of ballastless track, leading to deviations in the calculation of middle and high frequency vibration. This paperproposes a vehicle-flexible track coupling model and compares it with the vehicle dynamic model (vehicle-rigid track model). In the rigid track model, onlythe track irregularities are considered in the track module; the vibrations and deformations of rails, track slab and the foundation are considered in theflexible track model. Taking Chinese CRH3 series wheel profile S1002CN and rail profile CHN60 as examples and considering different track excitations,the two models are compared. The wheel-rail interaction forces, wheel-rail wear depths, wear volumes and vehicle accelerations are chosen as analysisindices for the comparative study.The results show that the wheel-rail forces of the flexible track model are larger than the rigid track model in the frequency range from 70 to 120Hz, whilethey decrease obviously in the frequency range above 150Hz. The differences in wear depths and volumes between the two models exceed 10%. Therefore,the flexible track model should be considered when studying the match properties of different wheel-rail pairs.