• Journal of KSNVE
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• v.10 no.3
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• pp.517-522
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• 2000

This study is concerned with the acoustic characteristics for recently developed interference-type noise barrier (T-shaped). To modify the previous shape more conveniently the T-shaped noise barrier with tuning partitions was examined in detail by varying the number and the hight of tuning partitions. The 2-D boundary element method(BEM) analysis were compared with the experimental results of 1/10 reduced scale model.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.1
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• pp.94-100
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• 2008

Noise barriers are being used more often to solve problems of noise pollution from traffic noise. Several types of noise barriers are being installed to increase the cost-effectiveness of noise barrier installation. In this study, the insertion loss is analyzed to evaluate the effectiveness of the noise barrier by using the BEM. In order to check the validity of the BEM, the BEM and Lam's theoretical analysis are compared with measurement, which is performed in the anechoic chamber for the 1/10 scale-down model, and good agreements are obtained. By using the two dimensional boundary element method, the insertion loss is calculated and analyzed for several typical noise barriers such as the vertical barrier, the barrier with an oblique edge on top, the T-shaped barrier and the barrier with interference device on top. With these analyses, it is possible to design more cost-effective noise barriers appropriate for a particular area.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.376.1-376
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• 2002

Reduction of the propagation noise generated during pass-by of KTX by noise barrier was measured and analysed fur the two kinds of top-shaped noise reduction devices; one as a plywood board and the other as a PVC pipe were placed periodically. The height and length of reference noise barrier are 2.4 m and 50 m, respectively. The noise reduction with and without noise reduction devices was investigated. (omitted)

• The Journal of the Acoustical Society of Korea
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• v.21 no.7
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• pp.624-631
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• 2002

The insertion loss of the noise barriers with several top shape is measured in an anechoic room by using a reduced scale model test. The insertion loss differences between a straight vertical barrier having 0.3 m height and several barriers with simple top shaped are compared. The results show that the latter is more effective than the former and absorptive barrier is more effective than the reflective one. Among the barrier types of 'T', 'Y', and '(equation omitted)', type 'Y' is the best one and the rest have similar effect. This result is well agree with Alfredson (PIOC. Inter-Noise 95, p. 381, 1995)'s but contradict to May (J. Sound Vb. 71, p. 73, 1980)'s. Therefore, it is difficult to determine which type is the best. In order to find out this discrepancy, boundary element method is adopted and the result shows one can have different result because each supposed different experimental conditions like height of noise barrier, positions of sound source and receiver, etc.