HAN Yan1,2,BU Xiumeng1,WANG Lidong1,2,3,LUO Ying1,2,LI Kai3
JOURNAL OF VIBRATION AND SHOCK. 2024, 43(5): 1-11.
Track unevenness is one of the primary sources of excitation that induces coupling vibrations in the vehicle-bridge system. The sensitive wavelength of the coupling vibration in the system has been identified, which holds significant reference value for line management. Firstly, a spatial model of the high-speed maglev train-track beam coupled system is established. In this model, the maglev train is simulated as a multibody dynamic model with 537 degrees of freedom, while the track beam is simulated as a spatial finite element model. The two are coupled through the magnetic track relationship based on PD control theory. Secondly, the Shanghai high-speed maglev is used as the research background, and a 5-car marshalling train crossing a 20-span simply supported girder bridge is selected as the calculation condition to verify the correctness of the model by comparing it with the measured results. Finally, considering the uneven excitation of track harmonics, the effects of different combinations of track unevenness in various directions, different amplitudes of track unevenness, and different vehicle speeds on the sensitive wavelength of dynamic response and ride stability of trains and bridges are discussed. The results indicate that the coupling of lateral and vertical vibrations in the maglev-bridge system is weak. At a design speed of 430 km/h, the sensitive wavelengths of the car body in vertical, roll, and pitch accelerations are 140-180 m, 60-100 m, and 120-160 m, respectively. The sensitive wavelengths of the car body in lateral and yaw accelerations are greater than 200 m. Resonance in the body roll, yaw, lateral, pitch, and vertical directions can be triggered at wavelengths of 80 m, 105 m, 115 m, 140 m, and 160 m, respectively. The response amplitudes of the car body and main beam are generally linearly related to the amplitude of track unevenness. When the amplitude of track unevenness is 1 mm, the peak roll acceleration of the car body does not change significantly with vehicle speed, while the peak accelerations in the other four degrees of freedom decrease with increasing vehicle speed. The vertical acceleration amplitude of the main beam increases linearly with vehicle speed. The lateral and vertical Sperling indicators of the car body indicate that the Sperling index of the car body is less than 2.5, indicating good ride stability for the maglev vehicle.