Abstract
In this paper, in order to reduce the ground vibration caused by Shinkansen running, we executed some measures as a part of the maintenance of the railway track in the tunnel, and verified the effect. First of all, lower stiffness rail pad was adopted replacing the current one to soften the track stiffness in vertical direction. As a result of the measurement, the vibration of 50Hz band reduced in the tunnel. On the other hand, the vibration corresponding to the wavelength of 2.5m was prevailing. Then, by evaluating the rail surface irregularity by using axle-box acceleration, we found that the irregularity of it wavelength is large for a part of rail. Next, in order to reduce the excitation load acting on the track caused by the irregularity, these rails were ground or replaced. As a result of the measurement afterwards, the vibration of 12.5Hz band reduced in the tunnel. Finally, it was confirmed that by these measures the ground vibration in the residential quarter on the upper part of the tunnel decreased by 6 dB on the average.
