Field measurements of maglev train-induced vibrations

Maglev line, one of the most advanced transportation systems, offers competitive journey-times to the railway and subway systems in the line length range of 60-1000 miles owing to its high acceleration and speed, but such a system may come with potential adverse vibration impacts. Field measurements of maglev train-induced vibrations were therefore performed on the world‟s first commercial maglev line in Shanghai, China. Seven test sites (sections) along the maglev line were selected according to the operating conditions. Vibration levels of bridge pier and nearby ground were measured in three directions. The attenuation of ground vibration was also investigated by measuring ground vibration up to 30 m from the track centerline. The measurement results of bridge pier and ground accelerations induced by high-speed maglev train (HSMT) running over the elevated guide way with speeds varying from 150 to 430 km/h were analyzed. Effects of maglev train speed on bridge pier and ground vibration were investigated in terms of their peak accelerations at a given test section. Effects of guideway configuration on bridge pier and ground vibration were also investigated by analyzing the measurement data when the maglev train ran at a speed of 300 km/h through two different test sections. The results showed that peak accelerations responses exhibited a strong correlation with train speed and distance from the track centerline. Guideway configuration had a significant effect on perpendicular vibration but weak impact on vertical and parallel vibrations of both bridge pier and ground. Statistics indicated that contrary to the commonly accepted theory and experience, vertical vibrations were not always dominant and perpendicular and parallel vibrations should be included, particularly at the corner of maglev line.