Blasting sound reducing device and method for reducing blasting sound in a closed space

摘要

PROBLEM TO BE SOLVED: To mitigate a blasting sound in a tunnel-like long closed space, and provide a blasting sound mitigating device of a simple configuration.SOLUTION: A blasting noise mitigating device is installed in a tunnel-like long closed space for mitigating a blasting noise in the closed space, and includes a tubular member with both ends open and a tube length from an opening on one side to an opening on the other side set to be half a wavelength of a frequency number of the sound to be mitigated. The opening on one side and the opening on the other side of the tubular member are located on a same cross-section in an axial direction of the closed space. A soundproof door is provided at a pit mouth of the closed space. At least one of the tubular member is installed along the axial line of the closed space, from the pit mouth toward a tip side of the closed space, leaving an interval that equals to half the wavelength of the frequency number of the sound to be mitigated.SELECTED DRAWING: Figure 1