Development of frequency-domain source models for railway vibration impact assessment

Many studies have been focused on the development of vibration source models, which comprise both the force applied on the track top and the vibration behaviour of the fixation system. Numerous researchers model the interaction between wheel and rail as a constant load moving along the track. Other authors consider a combination of harmonic and non-harmonic moving axle loads. Whereas most of these models are intended to validate time-domain vibration results, they become useless for predicting the frequency-domain vibration impact far from the track, data which is required in order to asses the fulfilment implied by most of the national regulations. In this work, two source models are presented and described. The first model comprises a series of empirical-statistical models, based on vibration measurements carried out in rail tracks. These models allow predicting the mean frequency-dependent applied force by high-speed, conventional and underground rolling stock. The second model consists in an analyticdeterministic approach based on the theoretical model of the wheel-rail deformation. This deformation is used to obtain the wheel-rail contact force trough the Hertz’s Theory of mechanical contacts. The model includes the superstructure motion, considering the rail as a Bernoulli-Euler beam, the sleepers as a punctual mass, and the pad, ballast and ground impedances. These source models will be included in the prediction tool for evaluating the vibration impact for new railway infrastructures, which is being developed within the CATdBTren project. This project has been awarded a R&D funding from the Catalonian Governmen.Peer Reviewe