近年來，全球暖化與氣候變遷導致極端天氣事件日益頻繁，強降雨與颱風造成的邊坡破壞與土石災害屢見不鮮，且多在短時間內降下豪雨引發大量土石滑動，對生命財產安全構成重大威脅。本研究以台南關子嶺地區具崩塌潛勢之邊坡作為對象，針對其潛在滑動機制與崩塌範圍進行模擬與分析。研究採用離散元素法（Distinct Element Method, DEM）為基礎的三維數值分析軟體 3DEC（Three-Dimensional Distinct Element Code）建立邊坡模型，模擬重力作用下塊體沿弱面滑動之行為，並設定不同弱面摩擦角（10°、15°、20°）進行分析，以探討摩擦角變化對邊坡穩定性與崩塌範圍之影響。
此外，為提升模擬結果之可讀性與應用性，本研究結合 Unity 軟體進行模擬成果之三維可視化，動態呈現滑動歷程、崩塌範圍及可能波及區域，強化地形理解與災害溝通能力。模擬結果顯示，三種摩擦角條件下均可能產生滑動現象，其中以上邊坡最先發生破壞，觀察點位移量明顯，少數塊體可滑動至下方白水溪地區。市道172線道路及鄰近聚落皆位於潛在影響範圍內，應列為優先監測與防護區域。
綜合模擬結果與地形條件評估，關子嶺邊坡具顯著崩塌風險，建議未來應加強地質調查與動態監測，並將數值模擬成果作為災前風險管理與災後應變規劃之參考依據，降低地方災害並保障居民安全。

In recent years, global warming and climate change have led to an increasing frequency of extreme weather events. Intense rainfall and typhoons have frequently triggered slope failures and debris disasters, often resulting in rapid mass movements within a short period and posing significant threats to lives and property. This study focuses on a potentially unstable slope in the Guanziling area of Tainan, Taiwan, aiming to simulate and analyze its potential sliding mechanism and failure extent.
A three-dimensional slope model was established using the Three-Dimensional Distinct Element Code (3DEC), a numerical analysis software based on the Distinct Element Method (DEM). Simulations were conducted to evaluate slope failure behavior under gravitational loading, with sensitivity analysis performed by assigning different joint friction angles (10°, 15°, and 20°) to assess their influence on slope stability and collapse extent.
To enhance the interpretability and applicability of the simulation results, Unity software was employed to create a 3D visualization of the failure process, including the sliding sequence, collapse extent, and potentially affected areas. The results indicate that slope failure may occur under all tested friction angles, with the upper slope being the first to experience displacement. Observation points showed significant movement, and in some cases, blocks slid down to the Baishuixi stream. Provincial Road 172 and nearby settlements fall within the affected zone and should be prioritized for monitoring and mitigation.
Based on the simulation results and terrain assessment, the Guanziling slope exhibits a high risk of collapse. It is recommended that future efforts include more comprehensive geological investigations and real-time monitoring. The numerical modeling outcomes can serve as a reference for pre-disaster risk management and post-disaster response planning to enhance local disaster resilience and ensure public safety.

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