Vibration response and mitigation strategies research for medium-low speed maglev trains under single-point levitation failure

In the current medium-low speed maglev engineering, direct collisions between medium-low speed maglev trains and tracks due to levitation failure often occur. This paper aims to analyze the dynamic response of the vehicle-bridge coupled system under single-point levitation failure and to propose vibration mitigation measures to reduce vibration and impact within the system. First, a medium-low speed maglev vehicle-bridge coupled model was established, considering flexible track beams, track irregularities, the levitation control system, and single-point levitation failure. The accuracy of the model was verified using operational data. Subsequently, the vibration response and impact were analyzed of the vehicle-bridge coupled system model under single-point levitation failure. Two vibration mitigation measures were then proposed, and their effectiveness was investigated. The results indicated that, through measure 1, measure 2, and their combined application, the vertical vibration acceleration of the cabin was reduced by 43%, 47%, and 51%, respectively. The vertical vibration acceleration of the bridge was reduced by 41%, 51%, and 66%, respectively. The maximum impact force was reduced by 46%, 66%, and 89%, respectively, with a maximum reduction of 13.97 kN. The vibration reduction measures proposed in this paper can provide a reference for vibration mitigation in medium-low speed maglev trains with mid-mounted suspension (MTMS) under levitation failure conditions.