以木塑材建構植生牆之吸音性能探討

Sound Absorption Performance of Green Walls Constructed with Wood Plastic Composites

張嵐婷(Lan-Ting Chang)

指導教授 ： 張豐丞

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201802614

摘要

回收塑膠製木塑複合材料（recycled plastic based wood plastic composites, rWPCs）被期望於取代傳統的高碳足跡材料，為了擴展rWPCs的應用領域，考慮其具有多孔材料的特性，因此對於其聲學性質進行研究，且考量到其機械強度，在本實驗中將rWPCs作為植生牆(LWS)的支撐體，用以發展低環境影響的全頻吸音構造。首先本實驗以阻抗管測量rWPCs及其與常見聲學結構的吸音效果進行較小尺度的測試，接著在迴響室中測量rWPCs和其作為LWS支撐體整體結構的吸音係數，以便了解其於實際應用上的吸音性能。結果顯示，rWPCs在中低頻範圍內具有中等吸音性能，其中空結構有利於輕量設計，而裝飾或功能表面紋路均有利於吸聲。另一方面，聲學結構的研究顯示小於3cm的空氣層和低穿孔面積(小於1%)對於rWPCs吸音改善具有相當的效果。最後，以rWPCs為支撐系統的LWS具有全頻範圍吸音能力，並且考慮支撐體、植生牆設計和植生覆蓋率對於聲學性質是必要的。

關鍵字

木塑材 ； 吸音性能 ； 植生牆 ； 阻抗管 ； 餘響室

並列摘要

Recycled plastic based wood plastic composites (rWPCs) is expected to replace conventional high carbon foot print materials. To expand the application field of rWPCs, considering its porous structure, the acoustic properties of rWPCs have been examined. Also, rWPCs has sufficient mechanical strength, therefore was applied as supporting system for living wall system (LWS) to create sound absorption element with low environmental impact in this study. First, the sound absorption coefficient of rWPCs and its combination with several common acoustic mountings was measured by impedance tube. Second, selected rWPCs and LWS with rWPCs integrated as supporting system were tested in reverberation room for understanding their sound absorption performance within a practical scale. It was found that rWPCs had medium sound absorption property at mid-low frequency range with its hollow structure beneficial to lighter design, while decoration or functional surface patterns were both favorable for sound absorption. On the other hand, the result of acoustic mountings suggested that air gap less than 3 cm and perforation area of less than 1% would be sufficiently effective for rWPCs sound absorption improvement. At last, LWS with rWPCs as supporting system was successful combination for full frequency range sound absorption, and for acoustic purpose, it would be necessary to take supporting system into account as well as garden module design and coverage rate.

並列關鍵字

wood plastic composites (WPCs) ； sound absorption ； living wall system (LWS) ； impedance tube ； reverberation room

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