Coupling vibration analysis of single-magnet suspension vehicle-bridge for maglev train

In order to study the coupling vibration of single-magnet suspension vehicle-bridge, suspension control system, vehicle structure, elastic track beam and bridge installation system were taken as a whole system, and maglev train suspension control-elastic bridge-mechanical structure vertical coupling vibration model of whole system was established.The effects of maglev train at different speeds on birdge were simulated by using external loads with different frequencies.The changes of mid-span deflection and vibration acceleration for different beam types were analyzed under the coupling condition of whole system.Study result shows that the mid-span deflection of simple-supported beam is about 2.5 times as the suspension position deflection of two-span-continuous beam when single-magnet suspension process achieves stable state.When train passes bridge at the speed of 200 km·h^-1, the deflection is slightly smaller than that at the case of 400 km·h^-1, the time that requires to achieve stable state for former case is about 1/3 of latter case.The mid-span deflection at suspension position for continuous beams is about 40% of the deflexion for simple-supported beam when train passes bridge at an identical speed, and the vibration acceleration of former case is smaller than that of latter case.The range of bridge critical mounting stiffness in simulation process is from 5.5×10⁷ N·m^-1 to 6.5×10⁷ N·m^-1, and the dynamics performance of two-span-continuous beam is better than that of simple-supported beam.