Propagation Law of Ground Vibration in the Switch Area of Metro Depot Based on a Field Test

A field measurement was carried out at switch area of Xiajiao Depot of Guangzhou Metro Line 3 to study train-induced ground vibration. The propagation law of ground vibration was investigated in the time-domain and frequency. It was found that the vibration values in two directions attenuate with the distance from the centerline of track, and there are tiny amplified zones at 17 m in the vertical vibration and 23 m in the horizontal vibration. Both the vertical vibration and horizontal vibration should be simultaneously taken into account in the environmental evaluation of the switch area of the metro depot. The frequency corresponding to the peak values of vibration decrease with distance from the centerline of the track and appear at 38-50Hz. In the measuring range of this test, the main frequency range of horizontal vibration is wider than vertical vibration. Compared to other straight rail (no rail switch) test results, the result of this test has broader frequency range.