Study of the influence of sleepers' material on track dynamics through numerical simulations

Abstract

Different track typologies compel different dynamic behaviors. Thus, the sleepers' material can play a key role in the wheel-rail contact forces and vibration generation phenomena. Furthermore, this situation can be increased if the vehicle speed is varied, accelerating track damages and maintenance operations. In order to assess the influence of sleepers' materials and vehicle speed on the vibration generation phenomenon, this paper develops a vehicle-track interaction model by means of a Finite Elements model in ANSYS commercial software. The numerical model is calibrated and validated with real data and then used to compare the different response of a ballasted track with concrete and wooden sleepers and accelerating and braking trains in both time and frequency domains. The results indicate the importance of sleepers' stiffness in the vibration generation phenomenon as well as the low sensitivity of vertical deflections to variations in the train speed.