2009 年 8 月 8 日，莫拉克颱風侵襲臺灣並帶來大量的降雨，整個颱風期間的累積降雨量幾乎達到臺灣的年降雨量，而此次颱風也造成許多自然災害。其中，位於臺東縣金峰鄉的包盛社發生大規模的崩塌。此崩塌面積約為250公頃，整個崩塌的土體量超過1000萬立方公尺，土體阻塞了下游的河道，形成堰塞湖。
本研究利用耦合尤拉-拉格朗日法來模擬包盛社崩塌。此方法是近年來用於解決工程問題的一種數值方法，它避免了傳統數值方法使用拉格朗日分析框架的缺點，像是：網格扭曲和變形；耦合尤拉-拉格朗日法結合了尤拉和拉格朗日分析的優點，除了避免網格扭曲的發生，同時也大幅減少了模擬時的運算時間。
而本研究區域包盛社的地質為畢祿山層，其以板岩、千枚岩及變質砂岩組成，其中板岩為最大占比，因此本研究以板岩材料為模擬的材料參數，討論了不同材料參數（內聚力、摩擦角和楊氏模數）對模擬結果（速度、沉積範圍和崩塌時長）的影響。根據不同的材料參數，總共有 27 種參數組合，並將這些參數組合的模擬結果與前人的文獻進行比較。最後本研究發現凝聚力是對整個模擬結果影響最大的材料參數。

On August 8, 2009, Typhoon Morakot brought heavy rain and induced many natural hazards. Among them, a large-scale landslide occurred in Bao-Sheng-She, Jin-Feng Township, Taitung County, Taiwan. The collapsed area of the Bao-Sheng-She landslide was 250 hectares, and the sliding mass was more than 10 million cubic meters.
In this study, the Coupled Eulerian-Lagrangian approach was used to simulate the Bao-Sheng-She landslide. This technique is a numerical method that has been used to solve engineering problems in recent years. It avoids the disadvantages of the traditional Lagrangian analysis framework, such as mesh distortion and deformation. The CEL approach combines the advantages of the Eulerian and Lagrangian analysis.
The study discusses the effect of different material parameters (cohesion, friction angle, and Young's Modulus) on the simulation results (velocity, deposition range, and collapse duration) of the landslide. A total of 27 combinations of the parameters were evaluated and compared with each other and to previous literature studies. Based on this study, cohesion was found to be the most influential parameter with respect to landslide velocity, deposition, and sliding time.

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