earticle

영어

Numbers of people living in high rise apartments are growing due to the overcrowding in urban area. Acoustic environment in those residential buildings has been seriously deteriorated by the increase of wheeled transports. According to the noise in urban area, higher performance of sound proof panel is needed. Commonly sound proof panel is applied to regulation of KS 4771-4. In this study, sound absorption coefficient of sound proof panels were studied. Regulation used sound absorption coefficient of sound proof panels must apply the four frequency ranges (250,500,1000,2000㎐). And the average value of sound absorption coefficient have to over 0.7 in the four frequency ranges. But this regulation has a limitation in evaluating the each frequency ranges. Through the measurement, even though absorption coefficient of one or two low frequency ranges are very low, the regulation of sound absorption coefficient is satisfy that the average value of sound absorption coefficient is over 0.7. As a results of traffic noise measurements, traffic noise level of bus and truck is over 80dB(A) in the 250Hz and over 65~68dB(A) in the 125Hz. So It is expected that the criteria of sound absorption coefficient in each frequency ranges and considering low frequency range are needed.

한국어

방음판 흡음률 규정의 경우 250㎐, 500㎐, 1㎑, 2㎑m이 평균흡음률이 70% 이상이면 이를 만족시키는 것으로 규정되어 있다. 방음판 측정결과 특정 주파수 대역에서의 흡음률이 아주 높을 경우 다른 대역의 흡음률이 아주 작게 나타나더라도 70%를 만족하면 되는 것으로 나타났다. 그리고 도로교통소음 실측과 선행연구를 통해 대형차의 소음레벨이 저주파 대역에서 집중되어 있고 특히 250㎐대역이 80㏈(A)를 상회하며 125 ㎐대역에서의 소음레벨도 65-68㏈(A)로 나타나 각각의 주파수 대역의 최저 흡음률과 저음을 고려한 흡음률 규정이 필요할 것으로 판단되었다.