LAUSR

The deflection ratio of the bridge is an important design parameter influencing the stability of the low-to-medium speed maglev train by affecting the levitation gap. This study focuses on the dynamic interaction of the low-to-medium speed maglev train and bridges with different vertical deflection ratios and investigates the required bridge vertical deflection ratio for the stability of the maglev train. The experimental investigation is carried out first. Then, a numerical dynamic interaction model is established and verified based on the field tests. And then, the influence of the vertical deflection ratio of a 25 m simply supported girder on the dynamic responses is discussed, as well as the bridges with the same deflection ratio but different span lengths. Finally, the maximum deflection ratios for the bridges with different span lengths are proposed and also compared with that of the existing maglev lines around the world. The study shows that when the deflection ratio reaches a certain level, the dynamic responses increase dramatically. The proposed allowable deflection ratios of bridges with different span lengths can not only ensure the smooth running of the train but also reduce the costs.