TUNNEL BLASTING SOUND REDUCTION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a tunnel blasting sound reduction device capable of providing a sufficient reduction effect against ultra-low frequency sound of 10 Hz or less.SOLUTION: The tunnel blasting sound reduction device according to the present invention can be moved in a longitudinal direction in a tunnel. The device has a plurality of sound tubes for reducing a sound emitted from a sound source. Each of the sound tube is a hollow tube which has a closed one end to form a closed portion and opened the other end to form an opened portion. The respective sound tubes have length corresponding to 1/4 wavelength of sounds with a plurality of different frequencies emitted from the sound source. The sound tubes are installed along the longitudinal direction of the tunnel and arranged so that the opened portion is provided at a position where a sound pressure level of a sound with a frequency resonating with the sound tube reaches a peak in the tunnel.SELECTED DRAWING: Figure 1