| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that an influence of an outer frame for support reinforcement of a soundproof unit on a noise reduction effect is different in the case of mounting a soundproof unit on the top part of a soundproof wall by providing the optimal outer frame.SOLUTION: In a soundproof unit 1 configured of a flow resistance material mounted on the top part of a soundproof wall to exhibit a noise reduction effect and an outer frame for support reinforcement disposed at the outer periphery, the section of an outer frame 3a disposed at the top part of the flow resistance material is configured as a perforated board 6 formed with a plurality of holes 6a piercing in a board thickness direction. |
