Study on Devices to Reduce Pass-by Noise Along Viaducts with Snow-Removing Openings

In heavy snowfall areas in Japan, a new Shinkansen train network is scheduled to open in the near future. The construction of viaducts with snow-removing openings on the floor slab has been planned to effectively remove snow on railway tracks during the winter. However, the noise generated by Shinkansen vehicles is directly radiated from the openings. In this study, an attempt is made to understand the acoustical performances of devices to reduce the noise radiated from the openings using both laboratory measurements on scale models and field tests in full-scale with running Shinkansen vehicles. The effects of 14 types of devices on Shinkansen noise are investigated in the scale model studies and Shinkansen noise is effectively reduced by approximately 10 dB at locations below the viaduct and at 25 m to the side for devices with sound-absorbing materials. The effects of the devices on Shinkansen noise were almost equal in the field tests to those obtained in the laboratory measurements.