Lateral Vibration Characteristics of Lms Maglev Train-Track-Bridge Coupling System Under Speed-Up State: Experimental and Theoretical Investigation

Improving the running speed on the in-service commercial LMS maglev transit is the most cost-effective way to enhance the carrying capacity. The increasing speed will disturb the maglev train’s lateral guidance performance, and further affects lateral vibration performance of the train and track-bridge system. In order to explore the lateral coupling vibration of the LMS maglev train-track-bridge system under speed-up state, a filed test for Changsha maglev commercial express at various speeds is carried out and the test data of the lateral responses is analyzed. Then, the refined theoretical model of the maglev train-track-bridge coupling vibration system is established and proved through this experiment. Finally, lateral vibration characteristics and mechanism of the coupling system at 160 km/h under speed-up state are discussed. The researches indicate the coupling vibration model is reliable. Under speed-up state, lateral responses clearly improves when the operating speed is above 120 km/h, especially for the levitation frame and car body. The lateral vibration of sleepers is noticeably bigger than that of the bridge. The vertical irregularity will affect the lateral guidance force and the coupling phenomenon is formed. Appropriate control of the vertical track irregularity amplitude will actively lower the lateral dynamic responses of the coupling system. When the operating speed is 160 km / h, although the dynamic responses of the system increases, the steady guidance of the maglev train can still be ensured.