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Acoustic Performance Evaluation of Noise Barriers Installed Adjacent to Rails and Suggestion of Approximation Formula for the Prediction of Insertion Loss

근접 방음벽의 음향성능평가 및 삽입손실 예측을 위한 근사식의 제안

  • Received : 2016.08.08
  • Accepted : 2016.09.05
  • Published : 2016.10.31

Abstract

In this paper, an investigation was conducted to evaluate the acoustic performance of low height noise barriers installed adjacent to rails; an easy-to-use approximation formula was suggested for the evaluation of insertion loss (IL), instead of using the boundary element method. At first, the acoustic performance of the low height noise barriers was measured in an anechoic chamber using a scaled down model; the overall IL according to the source location was analyzed with the equivalent IL contour line. Using the measurement results obtained from the scaled down model, an approximation formula was suggested for the IL of low height noise barriers having various shapes. Also, the prediction program was validated through a comparison between the actual measurement results in the anechoic chamber and the prediction results. Finally, using the prediction program, an approximation formula for IL was suggested for the low height noise absorption barriers. Considering the frequency characteristics of the noise sources of the train, the absorptive low height noise barriers have a 'ㄱ' type shape, a height of 1.0m, and a length of 0.5m when they are installed on the structure gauge for the train.

Acknowledgement

Supported by : 국토교통부

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