近年來之大地震易產生嚴重的土壤液化現象並造成建築物結構破壞、大範圍噴砂及維生管線受損等災害（如1999年台灣集集地震、2008年中國汶川地震及2010年紐西蘭達菲地震），而一般認為土壤液化現象為嚴重的土壤非線性行為，所以土壤非線性相關研究即應特別受到重視。前人對於土壤非線性之研究多以雙站頻譜比法（Spectral Ratio Method）作頻譜比分析，但往往地震所產生之液化範圍皆很廣，導致參考站不易覓得。所以Wen et al.（2006）利用單站頻譜比法（H/V Spectral Ratio Method）作非線性分析，利用羅東大比例尺核電廠模型地震試驗（LSST）及日本港島（Port Island）之地震資料，發現弱震與強震的頻譜比之主頻有所差異，可利用強震的頻譜比，定性描述測站土壤非線性效應。而Noguchi and Sasatani（2008）將強震及弱震之平均頻譜比值，依不同頻段相除並加總，建立定量非線性參數（Degree of Nonlinearity of Site Response, DNSR），做為強震站對地震非線性效應的參考量。由於達菲地震之破壞型態與汶川和集集地震相近，故本研究預計利用集集地震時，台灣中部強震站收到之強弱震紀錄，建立各測站DNSR值，並比對台灣現有之測站淺層30公尺之平均剪力波速（Vs30）調查結果，找出之間的關係，對於僅有簡易測站分類的汶川地震測站及紐西蘭地震測站，作測站場址分類及非線性現象之參考。 The serious soil liquefaction phenomena were caused from recent large earthquakes, and induced structural damages, sand blasting and lifelines damage (Such as Chi-Chi Taiwan earthquake, 1999, Wenchuan China earthquake, 2008, and Darfield New Zealand earthquake, 2010). However, the phenomena of soil liquefaction should be related to non-linear site response. So, we should pay much attention to the soil non-linearity study. The Spectral Ratio Method was used for many previously non-linear studies. But, due to the wide region of soil liquefaction occurred during the large earthquake and the reference stations were hard to find. Wen et al. (2006) analyzed the strong motion data of Large Scale Seismic Test (LSST) array and Port Island by H/V spectral ratio method. The result showed the H/V spectral ratios of single station can qualitatively display non-linear soil site response. Noguchi and Sasatani (2008) calculated the ratios from strong and weak motion. And they constructed the Degree of Nonlinearity of Site Response (DNSR) from the summation of a frequency band. Due to damage type of the Darfield earthquake were similar with Wenchuan and Chi-Chi earthquakes. In this study, the strong and weak motions from central Taiwan during the Chi-Chi earthquake were calculated first. And the DNSR value from each station was compared with Vs 30 respectively for each station. The results can be applied to figure out non-linear site response for Wenchuan and New Zealand earthquakes. Especially for the strong motion stations which only had a few site conditions such as Wenchuan and New Zealand earthquake to be a reference of site class and non-linear response. 研究期間：10008 ~ 10107
