| 摘要 |
PROBLEM TO BE SOLVED: To provide a porous type sound absorber which is constituted by modifying a container, consequently has comparatively large size and can effectively absorb sound.SOLUTION: A porous type sound absorber 11 is constituted by opening a plurality of openings 2 on at least one side surface 1 of a container 10 having a door 3, then arranging block-shaped porous sound absorbing materials 4 side by side inside the container 10 so as to block up these openings 2. A water repellent sound absorbing material 5 is provided on an opening side surface of the block-shaped porous sound absorber 4, and can prevent intrusion into the container 10 inside. The plurality of porous sound absorbers 11 are installed in a tunnel while the openings 2 of the porous sound absorbers 11 face each other, and can absorb a sound source of various frequency ranges generated from a transport vehicle and a heavy machine vehicle passing through a transport passage T sandwiched by the containers 10. |
