臺灣於沿海、近海與離島都具優越之風力能源，而我國屬於海島型國家且自產能源缺乏，石化能源均需仰賴進口，開發此風力發電將能發揮其效益，因應政府再生能源政策，遂選定風力品質優良且規劃面積廣闊之彰化近海地區，規劃彰濱區與芳苑區兩個離岸風場。又臺灣處環太平洋地震帶西岸，地震可能引致海床土壤液化，而大型風力機組造價昂貴，風機損毀將導致發電廠停止運作，故評估風場之液化潛能有其必要性。
本研究採用簡易經驗分析法之Seed (1997)法、Tokimatsu & Yoshimi(1983)法以及NJRA(1996)作為離岸風場液化潛能評估方法，並配合不同加速度計算來源作為分析參數，其中包括國震中心建議地震分區圖之建議值，簡文郁(2001)之震源衰減公式計算值，以及SHAKE地盤反應分析程式分析所得之值，進行液化潛能評估，再依Iwasaki(1982)所提出之深度加權法計算液化潛能指數，建立彰濱先導型離岸風場之液化潛能分區圖，期作為我國未來離岸風力發電場設計參考之用。

As an island country, Taiwan lacks of fossil energy and has to import the energy from abroad. However, there are several places with superior wind energy in Taiwan where located in the coastal, in the offshore and island. Therefore, the development of the wind power to compensate the shortage of fossil energy is inevitable. According to the government plan on renewable energy, Changhua offshore area has been selected as the wind farm for the development of the wind power. There are two sites, Jhangbin site and Fengyuan site, including in the the proposed offshore wind farms.
However, Taiwan is located in the seismic belt of western Pacific rim; Several severe earthquake disasters have recorded in the proposed area of the wind farm. Earthquake may cause seabed soil liquefaction. The sea bed liquefaction may damage the structures of the wind turbines and the damage of the structures would cause power plants stop working. Therefore, it is necessary to evaluate the liquefaction potential in seabed soil of the proposed sites.
This study uses the simple empirical methods to evaluate the liquefaction potential of the sea bed soil in the offshore wind farm, which including Seed’s simplified method (1997), Tokimatsu and Yoshimi’s method (1983) and the method suggested by NJRA (1996). The ground peak acceleration for which the three empirical methods is needed is computed by three methods, which are NCREE suggested acceleration, attenuation formula and computer program SHAKE. Then, the liquefaction potential index are computed by using Iwasaki’s depth-influence method and set the divisional graphs of liquefaction potential in offshore wind farm. This outcome can be used for design in the offshore wind farm.

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