地震風險評估對都市在計算減少地震發生時造成的潛在損失評估上扮演者重要的角色。本研究之地震風險評估由三個主要參數組成，分別為地震危害度、暴露量模型以及脆弱性曲線。評估特定場址在一定年限下超越某一強地動值的機率，稱為地震危害度分析。而機率式地震危害度分析是將地震與地質資料，以統計方法或其他機率方法推求場址的結構物在使用年限下，遭受超過各程度的強地動值的機率，進一步推估某一再現週期下所遭受的強地動值。暴露度為暴露於災害下的資產。暴露度模型可以提供包含座標、建築物分布、人口分布以及建築物分類等資訊，是整個地震風險中的基礎資料庫之一。脆弱性曲線（Vulnerability Curve） 的概念最早被地震工程專家應用於描述地震中橋梁或建築物之損害可能性評估，以地震災害的觀點而言常稱之為易損性曲線，易損性曲線表達了不同類別的建築物在某一強地動因子下可能的破壞機率，並被廣泛地應用於地震早期災損評估及減災規劃上。其中建築物易損性曲線對於地震風險評估有著重要的影響。本研究首先利用1999年集集地震及2016美濃地震後建築物損害紀錄，根據不同建築物建材類型，以最大概似法迴歸出在不同最大地表加速度 (PGA)以及最大地表速度 (PGV)下建築物易損性曲線，對比過去前人評估台灣地震風險利用PGA的易損性曲線，以過去集集地震及美濃地震實際觀測得到的地動值，計算及對比地震風險的結果。本研究建立的易損性曲線所進行的風險評估結果除對比過去易損性曲線評估之結果有所下修外，其美濃地震損失評估結果也較接近於實際災損評估。本研究期望透由建立易損性曲線，討論風險評估結果，作為未來提供政府及相關防災政策之參考。;The assessment of the seismic risk for the city represent an important resources in order to measure the potential losses due to future earthquake. The evaluation of seismic risk involves the combination of three main components: seismic hazard model, exposure model defining the spatial distribution of elements exposed to the hazard and vulnerability functions capable of describing the distribution of percentage of loss for a set of intensity measure levels. Building fragility curve is an important component to influence the seismic risk. The fragility curves in this study will be made based on the building damage records collected from the 1999 Chi-Chi and 2016 Meinong earthquakes. The fragility curves in Taiwan were previously developed based on the value in peak ground acceleration (PGA). In the knowledge finding on the relation of hazard to damage as to be risk related, PGA is not a critical parameter for this estimation. In view of this, we intend to develop building fragility curves in other strong motion parameters (e.g., peak ground velocity or revised intensity). By using maximum likelihood estimation method we estimate the building damage and economic loss in comparison to the previously established PGA-based curves. In this case the reliability of the building damage and economic losses for our result are higher than the estimation from pre-existing fragility. We implemented both the pre-existing fragility curves and those we have obtained to the probabilistic seismic risk assessment for Taipei and Tainan City. Our intention is to give the new building fragility curves in different types of intensity and the first attempt on the modeling the seismic risk on an open platform for Taiwan.
