# 형상 방음벽 패널의 반사음 저감효과 평가

• Lee, Jaiyeop ;
• Kim, Ilho
• 이재엽 ;
• 김일호
• Accepted : 2015.10.02
• Published : 2015.10.15
• 12 12

#### Abstract

PURPOSES : The noise, which is typically generated by fast moving vehicles, can be intercepted by installing a noise barrier with a soundproof panel. However, reflections from the panels cause secondary noise, and hence lower the effectiveness of the panels. In this study, the reduction of reflection noise by considering the shape, especially zigzag one, of the soundproof panel have been evaluated. METHODS : The simulation model used in this study was Nord2000, which simulates real-road situations effectively. Based on the simulation results, the joining angle of $133^{\circ}$ with the pattern width (a) equal to 2 m and the projection height (b) equal to 0.5 m was adapted in the zigzag shape as the best profit designing factors. RESULTS: The measuring results at middle height, 15 m showed reduction at all points except the point with average -1.6 dB. At a greater height of 30 m, 2 points showed reduction. A real-sized facility was constructed to investigate the reflected sound from a zigzag shaped panel up to the height of 5 m. CONCLUSIONS: The reduction effects were detected in all the receive points in the range of 2-6 m distances and 1-5 m heights comparing the plane panel. Compared to plane panel, the noises are reduced at an average of 2.4 dBA.

#### Keywords

Noise barrier;Soundproof panel;zigzag shape;Nord 2000;shaped panel

#### References

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#### Cited by

1. Soundproof Characteristics of Zigzag-Shaped Panel on Site vol.40, pp.1, 2018, https://doi.org/10.4491/KSEE.2018.40.1.15
2. Parametric Applicability Assessment of High-Strength Steel Tubes of Noise Tunnel Structures for Weight Reduction vol.18, pp.7, 2018, https://doi.org/10.9798/KOSHAM.2018.18.7.299

#### Acknowledgement

Supported by : 한국건설기술연구원