• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.4
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• pp.371-388
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• 2003

The tunnels that longer than 2km which have been recently constructed have serious noise problems resulting from the friction of vehicle wheels and pavement. In special, concrete pavement inside tunnels with a closed characteristic increases discomfort due to the traffic noise and the dust of pavement pollutes the air in tunnels. Therefore, it is urgent that we find out ways to cope with. This study purported to reduce noise inside tunnels covers the investigation of various pavement surface treatment methods adapted in developed countries, the analysis of the effect in noise reduction and construction methods and cases. The surface treatment method for silent pavement in tunnels reduced noise to 5dB (A)~10dB (A). Aggregate treatment method is evaluated the most appropriate method in that, related with other surface treatment method, it reduces noise and improves skid resistance. It is necessary for us to introduce equipments and design and rearrange of specification for the development of the silent pavement method in Korea.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1927_1928
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• 2009

한국철도공사의 조사에 의하면 KTX 이용 시 승객들이 느끼는 가장 불편한 점 중에 하나로 소음문제를 지적하고 있다. 특히 한국은 프랑스 등 유럽 국가와 달리 터널 구간이 차지하는 비중이 높아 터널 구간에서의 소음이 심각한 문제가 되고 있다. 본 연구에서는 KTX 터널 구간 운행 시 발생하는 소음을 능동소음제어 기법으로 제어하는 가능성을 알아보기 위하여 안정도가 강화된 IIR LMS 알고리즘을 이용하여 KTX 소음을 저감하는 능동소음제어시스템을 제안하고, 이를 이용하여 직접 측정된 KTX 소음을 제어하는 컴퓨터 시뮬레이션을 수행하였다.

• Journal of Power System Engineering
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• v.16 no.5
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• pp.20-25
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• 2012

오늘날 고속 철도는 중요한 교통수단으로 사용되고 있다. 주행거리 단축을 위해 직선 선로를 만드는 것이 불가피해 졌고 그에 따라 터널과 교량의 구간이 늘어나게 되었다. 특히 터널 통과 시에 발생되는 실내 소음은 운행 속도, 운행 구간 레일의 종류 등 여러 가지 원인에 의해 야기되어 진다. 실내소음으로 인해 철도를 이용하는 승객의 쾌적한 환경에 많은 영향을 미치게 된다. 이에 본 연구에서는 KTX와 새마을호의 터널 통과 시 발생되는 소음이 피험자에게 미치는 영향을 EEG를 통해 살펴보았다. 먼저 터널 통과 시 KTX와 새마을호의 실내 소음을 실제로 측정하여 크기, 주파수별로 분석하였다. 측정된 실내 소음을 피험자에게 제시하였을 때 나타나는 EEG를 측정하였다. EEG의 분석에 대해서는 불안, 긴장 등 스트레스를 받을 때 강하게 나타나는 ${\beta}$파의 변화를 관찰한 결과를 제시하였다.

• The Journal of the Acoustical Society of Korea
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• v.26 no.5
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• pp.220-226
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• 2007

The two major objectives of acoustical measurements in a cavitation tunnel are measuring the noise levels generated by rotating propellers behind a hull and localizing possible noise sources in order to reduce noise levels. Propeller noise measurement experiments were performed in MOERI cavitation tunnel at December, 2006. In order to put the propeller into cavitating conditions, a wake-generating dummy body was devised. In addition, ten hydrophones are put inside a wing-shaped casing in order to minimize the unexpected flow induced self noise around hydrophone itself. After measuring both of the noises of the rotating propeller behind the dummy body and signals generated by a virtual source, respectively the data were matched field processed using the frequency incoherent Bartlett processor to localize noises on the propeller plane. In this paper, we presented the measured noise analysis and the localization results.

• Journal of the KSME
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• v.34 no.10
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• pp.796-807
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• 1994

이 글에서는 고속철도 터널에서 열차에 의해 발생하는 압축파의 특성과 그의 전파거동에 관하여 기술하였다. 또 터널내에서 발생한 압축파가 터널 출구에서 충격음(미기압파)으로 방출되어 주 변의 환경에 큰 영향을 미치고 있다는 문제점을 지적하였으며, 이러한 소음의 발생 메카니즘과 소음의 저감 및 제어방법에 대하여 개괄적으로 기술하였다.

• Explosives and Blasting
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• v.25 no.2
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• pp.23-33
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• 2007

It is difficult to measure a blast noise in the vicinity of tunnel blasting works and the effect of lowering noise changes very highly with types of soundproof materials. So, the main interest of this study focuses on the materials of a soundproof facilities and the method of noise forecast in a near distance. 20 types of the soundproof facilities are established and blast noise is generated using firecracker in a Hume concrete pipe. To analyze the variations of magnitudes of noise and frequency with the soundproof materials and types, the noise and frequency is measured in a short distance next to blast area.

• Journal of KSNVE
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• v.3 no.2
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• pp.95-102
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• 1993

고속철도를 포함한 철도운행에 있어서 소음문제는 중요한 환경문제의 하나 이다. 지금까지 철도소음에 관한 국내에서의 연구는 철도소음 기준과 관련된 일부 연구를 제외하고는 거의 없는 상황이다. 앞으로 고속철도의 성공적인 운행을 위하 여는 선로변에서의 소음저감 대책으로 지형과 궤도조건에 따른 소음피해 예측과 소음원 특성을 고려한 효과적인 방음설계에 대한 연구가 필요하다. 또한 경부고속 철도 노선에 터널이 많으므로 터널 미기압파의 발생과 그대책에 대한 연구가 필요할 것으로 생각된다. 이와 더불어 국산화 차량 개발을 위하여 차체와 판토그래프에서의 공력소음감소를 위한 공력해석, 전동소음과 구조물 소음 감소를 위한 차륜과 쾌도의 개선, 추진장치와 보조장치의 소음제어설계 등 각각의 소음발생원에 대한 이해와 소음저감 기술의 개발이 필요하다.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.1
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• pp.111-117
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• 2000

In the KRISO cavitation tunnel, the acoustic characteristics for the measurement of underwater noise are investigated, The background noise is measured and analyzed up to 100kHz at various test conditions. The noise level of the KRISO cavitation tunnel is compared with those of the other cavitation tunnels which have been designed for the noise study[HYKAT(Germany), GTH(France), etc.]. In order to investigate the background noise source. the coherence between structural vibration and noise level is analyzed using the B&K 3550 FFT analyzer. The experimental results show the possibility of the noise study and suggest the improvement plan.

• The Journal of the Acoustical Society of Korea
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• v.37 no.4
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• pp.223-231
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• 2018

Recently, due to various environmental problems, blast tracks in tunnel are replaced with concrete tracks, but they have more adverse effects on noise than blast tracks so that additional noise measures are needed. Among these measures, sound-absorbing blocks start to be used due to its easy and quick installation. However, the performance of sound absorption blocks need to be verified under real environmental and operational conditions. In this paper, interior noise levels in KTX train cruising in Dalseong tunnel are measured before and after the installation of sound-absorbing blocks and the measured data are analyzed and compared. Additionally, noise reduction are estimated by modeling the high speed train, the tunnel and absorption blocks. Measurement devices and methods are used according to ISO 3381 and the equivalent sound pressure levels during the cruising time inside the tunnel are computed. In addition to overall SPLs(Sound Pressure Levels), 1/3-octave-band levels are also analyzed to account for the frequency characteristics of sound absorption and equipment noise in a cabin. In addition, to consider the effects of train cruising speeds and environmental conditions on the measurements, the measured data are corrected by using those measured during the train-passing through the tunnels located before and behind the Dalseong tunnel. Analysis of measured results showed that the maximum noise reduction of 6.8 dB (A) can be achieved for the local region where the sound-absorbing blocks are installed. Finally, through the comparison of predicted 1/3-octave band SPLs for the KTX interior noise with the measurements, the understanding of noise reduction mechanism due to sound-absorbing blocks is enhanced.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.1014-1019
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• 2003

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 area has been seriously deteriorated by the increase of traffic vehicles. Commonly used sound barriers have a limitation in controlling noise due to diffraction noise of sound barrier. Hence sound barrier is not effective to attenuate noise especially for the residential units in high level. This work aims at evaluating noise reduction according to the tunnel section shape by using 1/5 scale model. We carried out a number of field measurements for 1/5 scale model of Noise Barrier Tunnel with various sectional shape. The results from predictions and the measurement show generally good agreement.