Low-frequency vibration suppression performance of particle damper and M-PTMD designing for maglev steel switch girder

Particle damping technology is widely used for reducing high-frequency vibration, and has few applications in the field of maglev vehicle-bridge coupled vibration reduction. This study investigates the energy dissipation performance of particle dampers under low excitation intensities, with a particular focus on violent coupled vibration between maglev vehicle and switch girder. A discrete element model-multi body dynamics (DEM-MBD) co-simulation method is developed and validate through the proof concept experiment of particle damper-cantilever beam system. The effects of particle packing layer number, particle diameter, and chamber section geometric shape on energy dissipation are analyzed. A multi-particle tuned mass damper (M-PTMD) is specifically designed for the steel switch girder in medium-low speed maglev transportation systems, and its vibration suppression performance for maglev steel switch girder is evaluated. Simulation results indicate that a particle damper with three-layer particle packing, diameter of 12 mm and triangular chamber section can provide better energy dissipation characteristics under low excitation intensities. When the maglev train running through the switch girder at speed of 30 km/h, the proposed M-PTMD can reduce the acceleration of girder by 53.4% while that of M-TMD is 30.3%. The proposed M-PTMD can achieve superior vibration suppression performance in maglev vehicle-steel switch girder coupled dynamics system.