隔音牆頂邊裝置對繞射音場改善之研究

Improving diffracted sound over a barrier by installing specially designed devices

賴明正(Ming-Cheng Lai)

指導教授 ： 陳國在

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01988

摘要

本文根據新型隔音牆的設計概念，以二維之邊界元素法分析這些新型的裝置對隔音牆繞射音場的改善情形。其次並實際架設隔音牆，以進行這些新型的設計概念對繞射音之改善實驗測定。根據數值解析結果，這些新型的隔音效果，均較一般標準型隔音牆具0.51~4.82dB之更佳效果; 而隔音牆實驗測定結果，雖與數值分析結果具差異性，然而其衰減量增加的趨勢與數值分析的結果甚為相似。

關鍵字

隔音牆 ； 繞射 ； 邊界元素法

並列摘要

Upon the design concept for new type barriers, this study uses a two dimensional boundary element method to analyze the improvement on the diffracted sound field over those barriers when installing some special devices on them. Further more, the corresponding measurements are made when the actual barriers involved are constructed. From the numerical result as obtained, it shows the acoustic protection performance for the new type barrier is greater by 0.51 to 4.82dB than that of the standard type barrier. Though there is some discrepancy of the measurement from the numerical result for every barrier, the increment tendency of acoustic attenuation of barrier for the two results as obtained is very similar.

並列關鍵字

noise barrier ； diffraction ； BEM

參考文獻

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