• KIEAE Journal
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• 제2권1호
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• pp.55-61
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• 2002

It seems inevitable for residential buildings to be high-rise and allocated near traffic roads due to the overcrowding in urban area. Acoustic environment in those residential buildings has been seriously deteriorated by the increase of traffic vehicles. Commonly used sound barriers have a limitation in controlling noise diffracted over the boundary of a sound barrier and hence are not effective to attenuate noise especially for the residential units in high level. The use of an enclosed noise barrier can be an alternative to supplement the defects of conventional noise barriers. The present work aims at providing useful data in designing enclosed noise barriers for residential areas adjacent to roads. Number of field measurements for various noise barriers and enclosed noise barriers were carried out and the results were discussed with relation to the proper design of enclosed noise barriers.

• 소음진동
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• 제8권1호
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• pp.146-156
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• 1998

자동차의 폭발적인 증가와 아울러 경부고속전철시대를 맞이함으로 인하여 소음공해는 큰 사회적 문제로 대두되고 있다. 본 연구는 이러한 소음공해에 대한 해결책의 일환으로 효율적인 방음벽을 연구 하는데 그 목적이 있다. 방음벽의 연구는 먼저 반사형 방음벽과 흡음형 방음벽에 대한 소음저감효과 를 산정한 다음, 흡음재료를 사용함으로서 감소되는 소음저감 효과를 산정하는데 큰 의의가 있다. 본 연구결과에 의하면 방음벽의 높이에 비하여 음의 파장이 대체로 짧을 때는 방음벽의 상단부분에 흡음재를 설치하면 방음벽 전체에 흡음재를 설치한 것과 같은 효과가 있다는 결론을 얻었다. 도로교통소음은 평균주파수가 550Hz 이므로 이때 파장은 60cm 정도이다. 방음벽 높이를 4m로 설치했을 때 방음벽 상단에서 60cm 정도만 흡음재를 사용하면 4m전체의 방음벽에 흡음재를 사용한 것과 같은 효과가 있는 것으로 나타났다. 흡음재를 사용한 소음저감의 효과는 점음원이고 수음자의 위치가 $135^{\circ}$ 일 때 평균 8dB(A)정도이고, 선음원일때는 평균 3dB(A)정도의 효과가 있는 것으로 나타났다 이러한 흡음형의 방음벽은 경제적일 뿐만 아니라 방음벽의 높이를 최소한 1m이상 줄일 수 있으므로 국토를 고도로 이용해야 되는 우리 나라의 여건에 대단히 효과적인 방음벽이라 사료된다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.153-158
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• 2007

Sound insulation performance of the flush door in the apartment unit was recently decreased due to the door for the purpose of barrier free. To evaluate sound insulation, the test for 13 kinds of flush doors was performed as aperture conditions under the flush door. and the measured value was compared with the predicted values of theoretical sound transmission. The results were summarized follow; First, in case of doors with aperture by barrier free, the single number quantities ($D_{pw}$) were evaluated $21{\sim}23dB$. Whereas, in case of existing door with frame, $D_{pw}$ was evaluated $28{\sim}31dB$. And in case of sealed doors, $D_{pw}$ was evaluated $31{\sim}34dB$. Second, the measured $D_{pw}$ was good agreement with the predicted $D_{pw}$ in condition of small aperture.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.1081-1085
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• 2002

A modeling is developed to predict the isolation performance of sound barrier systems under the sound pressure radiated from excited by point impact. The predicted results are compared with the measured results obtained by using APAMAT II. This instrument provides a combination of structure-borne noise and air-borne noise, which corresponds to rolling noise, by applying the excitation system projected steel balls against the steel sheet.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.1026-1031
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• 2003

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. Commonly used sound barriers have a limitation in controlling noise influencing higher part of a residential building. The use of noise barrier tunnels can be an alternative to supplement the defects of conventional noise barriers. But intensive measurements on noise levels at apartments vicinity of current noise barrier tunnels show that the tunnel now has a limited advantage on reducing the noise levels from arterial roads. The present work aims at providing an useful design tool In designing noise barrier tunnels for residential areas adjacent to roads. Number of field measurements, scale model measurements, and computer simulations were performed to ensure whether the prediction from scale model and computer simulation are appropriate. Result shows that the predictions from scale models and computer simulations could be valid prediction tools for designing sound barrier tunnels.

• Environmental Engineering Research
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• 제20권4호
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• pp.383-391
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• 2015

Transparent type noise barrier is a desirable facility since it provides a secure view to drivers and passengers. However, reflection from this type of barrier could annoy dwellers on the sides of the road. To reduce reflection noise by transparent type barrier, modification can be made to the shapes on the front side and hence get effects by distortion of sound transmission. To achieve this, we have conducted simulation by which the effects of patterned screens of noise barrier on high-ways were investigated. The reduction effects of reflected sounds were evaluated for swelling, swelling with curved, rectangular and V-shaped screen type barriers, compared to the planar panel. The emitting noise was generated by 6-lane road and the patterned noise barriers had shown the reduction effects, especially in swelling and swelling with curved type for middle height dwellers, and the V-shaped screen type for higher elevation dweller. The swelling-type showed a decrease of 0.7~1.2 dB, performing the best diminution effect among the tested noise barriers.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.1180-1184
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• 2001

This paper presents the effect of air gap insertion on the results in measuring the transmission loss of sound barrier by using APAMAT. The measured results show that air gap insertion improves transmission loss as by two-room method or intensity method. The measured results are compared with the predicted transmission loss using MATLAB GUI program based on the transfer matrix method. Predicted results were found to be in reasonable agreement with measured results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.877-881
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• 2001

In this paper, a model is developed that can predict insulation performance of sound barrier systems under the action of multiple random point impact. The predicted results are compared with the measured results obtained by using APAMAT II. The results show the error due to the difference between experimental environment and theoretical assumptions. The model is needed to be improved to obtain better agreement between predicted and measured results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 I
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• pp.145-149
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• 2001

In this study, an acoustical characteristics of sound proof panel for high speed train was performed. A sound absorption coefficient and transmission loss of sound proof panels for high speed train were tested in reverberation chambers and compared those of ordinary sound proof panel. The effect of noise barrier was simulated by using ray noise program with measured sound absorption coefficient for high speed train case and for ordinary case.

• 한국음향학회지
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• 제21권7호
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• pp.624-631
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• 2002

방음벽의 상단부 형상에 따른 삽입손실을 무향실에서 모형축척 방법으로 측정하고 상호 비교하였다. 높이 0.3m의 수직형 방음벽에 대한 삽입손실과 간단한 형상물을 상단부에 설치한 방음벽의 삽입손실과의 차를 비교하였다. 실험결과 단순히 높이를 증가시키는 경우보다 상단부에 간단한 형상을 설치한 것이 더 효과적이었다. 'T'형, 'Y'형 및 '(equation omitted)'형 방음벽에 대한 삽입손실을 비교한 결과 'T'형과 '(equation omitted)'형 방음벽은 비슷하였으며 'Y'형이 가장 좋은 효과를 나타냈다. 본 연구결과는 Alfredson(PIOC. Inter-Noise 95, p. 381, 1995)등의 결과와는 잘 일치하지만 May (J. Sound Vib. 71, p. 73, 1980) 등의 결과와는 상충된다. 따라서 어떤 형태가 가장 좋은지를 결정하는 것은 어렵다. 왜 이러한 상호 모순되는 결과를 얻게 되는가를 알기 위해 경계요소법을 적용한 결과 각 연구자들마다 다른 방음벽의 높이, 음원과 수음점의 위치, 높이와 거리를 서로 다른 실험조건을 가정했기 때문임을 알 수 있었다.