極端的降雨事件常誘發山坡地發生崩塌災害，以極限平衡法作為計算理論的數值分析，是常見用來分析邊坡穩定性的方式之一。本研究採用TRIGRS與Scoops3D數值分析軟體，前者可運用於分析降雨期間邊坡地下水位的連續狀態，後者則可用於建構符合邊坡地質條件之數值模型並計算安全係數。
本研究透過結合TRIGRS與Scoops3D的優點，分析高雄燕巢泥岩崩塌邊坡、嘉義中心崙潛在大規模崩塌邊坡，以及嘉義檨仔寮地表變形邊坡等案例邊坡，在受到降雨影響時之穩定性的變化歷程。分析結果顯示 (1)燕巢泥岩崩塌邊坡受到2016年梅姬颱風影響的期間，崩塌邊坡之不穩定區域的發展歷程及崩塌時間，均接近真實崩塌事件的調查結果；(2)中心崙崩塌邊坡受到2018年8月豪雨影響的期間，邊坡上不穩定區域的分佈與陡峭地形有關；(3)檨仔寮邊坡受到2013年潭美颱風及康芮颱風影響的期間，邊坡具有相同的穩定性趨勢。綜合以上研究結果，結合TRIGRS與Scoops3D進行邊坡穩定性之數值分析方式，能夠正確地反映邊坡之安全係數在受到降雨影響時的變化歷程，同時也反映地形對邊坡穩定性的影響。
此外，本研究也針對TRIGRS與Scoops3D兩模型的穩定性分析結果、參數設定，及模型設定對兩模型之分析結果的影響進行討論。討論結果顯示：(1)TRIGRS之穩定性分析的安全係數結果，普遍低於Scoops3D的結果；(2)影響TRIGRS之地下水位分析結果最甚的參數為土壤層厚度；(3)影響Scoops3D之安全係數分析結果最甚的參數為內摩擦角；(4)使用Scoops3D分析穩定性時，Fellenius法分析所得之安全係數結果，普遍較Bishop簡化法所得之結果低；(5)Scoops3D之搜尋配置的討論中，分析結果的影響主要受到水平乘數控制。

In recent years, frequent extreme rainfall events have often caused rainfall-induced landslides on mountain slopes. In order to reduce the impact of landslide disasters, limit equilibrium method is one of the common methods to evaluate the slope stability. With the vigorous development of computer and numerical analysis, not only the efficiency of the slope stability calculation process is improved, but the visualization of the analysis results can directly realize the unstable area on the slope. TRIGRS and Scoops3D are applied in this study for analyzing the progression of the factor of safety (FS) during the period when the slope is affected by the rainfall event. TRIGRS is able to calculate the continuous situation of the groundwater level during the rainfall event. Besides, Scoops3D is able to construct a model based on the geological conditions and calculate the FS of the slope.
Three cases were analyzed in this study, including Yanchao mudstone landslide slope, Jhongsinlun potential large-scale landslide slope, and Shezailiao surface-deformed slope. According to the results, during the period when Yanchao slope was affected by Typhoon Megi in 2016, the progression of the FS and the moment when landslide occurred were consistent with the practical record. During the period when Jhongsinlun slope was affected by the rainfall event in August 2018, the distribution of low FS on the slope was related to the steep topography. During the period when Shezailiao slope was affected by Typhoon Trami and Typhoon Kong-rey in 2013, respectively, the FS of the cliff on the slope decreased while the accumulated precipitation exceeded 250 mm. On the other hand, the FS of the whole slope still maintained at about 1.50. Consequently, the combination of TRIGRS and Scoops3D can analyze the progression of the FS while the slope is under the influence of rainfall, and also reflect the influence of terrain on the slope stability.

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