Experiment and analysis of train-induced metro depot vibration

Vibration induced by metro propagates to the building and affects people’s normal life and work, which has become a key factor restricting the development of over-track building. Relying on an over-track building project in Southwest China, vibration experiments are carried out in turnout area, parking area, over-track area and sensitive area of the metro depot. Acceleration and vibration level are selected as indicators to study the propagation law of vibration in depot structure and evaluate the impact of vibration on depot. The vibration amplification phenomenon of the over-track platform is studied and the functional relationship between the vibration amplification position and the wave velocity, frequency, and bearing column spacing is constructed. Results show that the vibrations of the turnout area are obviously greater than other areas, the maximum vibration is 100.3 dB on the rail. In the process of vibration propagating from the rail to the bearing column, the attenuation increases with the increase of distance, and the vibration is attenuated in the range of 1.25 Hz−200 Hz. The phenomenon of vibration amplification exists at the over-track platform, the maximum z-vibration level is amplified by 4.3 dB at most, which is considered to be caused by the vibration superposition in the depot structure. For the structure studied in this paper, the vibrations with frequencies of 10 Hz, 20 Hz, 31.5 Hz, and 63 Hz cause local vibration amplification of the floorslab, and the maximum position of vibration superposition is related to wave velocity, frequency and bearing column spacing.