緣於我國推動離岸風力主軸計畫，風場場址的開發與建置將造成棲息於台灣西部沿岸的中華白海豚之威脅，故基樁建置過程勢必伴隨減噪工法以降低噪聲於環境生態之影響。過去常用之氣泡幕減噪工法礙於實際海洋場潮、流等影響造成包覆性不佳，以及低頻噪聲減噪效果不彰等問題，因此本研究的主要目的為針對基樁建置時之寬頻噪聲進行吸音材料套筒減噪工法研擬。本研究先以阻抗管對多孔性發泡材料篩選出合適之吸音材料，再以吸音材料套筒包覆基樁進行減噪，並以實驗方法分析吸音材料套筒原料差異、發泡倍率(孔隙率)、厚度等因素對寬頻聲波衰減之影響，於後加入環形氣泡幕共同進行減噪。本文實驗主要於國立成功大學水利及海洋工程學系光纖感測與聲學實驗室之強化玻璃纖維(FRP)水槽中進行，撞擊基樁以模擬基樁施工之寬頻噪聲，並由水下麥克風量測分析其通過吸音材料套筒之消音現象。研究成果顯示吸音材料套筒配合材料條件因素之選定其消音效果可達約30 dB以上之衰減，可單獨作為一減噪工法外，另外搭配環形氣泡幕包覆其中亦可增加其減噪成效。

In order to protect marine mammals from the underwater noise produced by driving the piles for offshore wind farms, this study investigates the use of porous sleeves for attenuating underwater noise and enhancing the effects of bubble curtains. Sleeves with various proportions of plastic and elastomer are tested. The material characteristics are discussed in terms of composition, expansion ratio (porosity), and thickness. Experimental results show that a porous sleeve can be used alone or in combination with a bubble curtain around a pile. Underwater noise can be reduced by about 30 dB with sleeve and bubble curtain in the frequency range of 250 Hz to 15 kHz.

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