Theoretical and experimental study on vibration reduction and frequency tuning of a new damped-sleeper track

Abstract

• A new elastic side-supporting long sleeper damping track (ESSDT) is proposed. • A vibration reduction and frequency modulation device (VRFMD) is applied to the ESSDT. • The vehicle-track coupled dynamics analysis is achieved by co-simulation. • The VRFMD can adjust natural frequency and improve dynamics performance of the ESSDT. In urban rail transit, it is important to reduce the train-induced vibration on ambient environment. To achieve this goal, a new elastic side-supporting long sleeper damping track (ESSDT) is proposed in this study. Besides, a novel vibration reduction and frequency modulation device (VRFMD) is also proposed to improve the vibration damping performance as well as structural stability of ESSDT. Based on the vehicle-track coupled dynamics model and the finite element model of ESSDT, dynamic characteristics of ESSDT are investigated theoretically. The influence of key dynamic parameters of VRFMD on the damping effect and stability of the track system are studied in detail. Further, a hammer test was conducted on a full-scale test rig of ESSDT with VRFMD. Test results validate the theoretical research results, which proves that both the vibration of track and the vibration transmitted to the foundation can be attenuated effectively due to the installation of VRFMD. The results show that the spring stiffness of VRFMD has great influence on the dynamic response to ESSDT. The natural frequency of ESSDT could be adjusted by modifying the parameters of VRFMD, which may provide a new approach to avoid wheel-rail contact resonance. Moreover, VRFMD may also be introduced to other types of track for the purpose of vibration reduction and frequency adjustment, such as floating slab track and ladder sleeper track.