地下水引发自由端顺向坡土体滑动特性分析 - 中华水土保持学会.PDF

110 中華水土保持學報, 45(2): 110-118 (2014) Journal of Chinese Soil and Water Conservation, 45 (2):110-118 (2014) 地下水引發自由端順向坡土體滑動特性分析 [1] [1] [2]* 陳樹群 陳冠翰 吳俊鋐 摘 要 由地下水誘發自由端邊坡滑動現象，崩塌型態屬於後退型崩塌。主要誘發因子為滲透水分造成下層 土壤流動化及地下水輸入管鄰近區域因土壤土體底層水分飽和度超過 29%而產生土壤下陷現象。在相同坡度 的邊坡滑動實驗中，地下水量越增加，達到邊坡滑動平衡的時間越短且發生滑動次數越少；而在相同輸入地 下水量的邊坡滑動實驗中，坡度越增加則達邊坡滑動平衡時間越短、有越高比例的滑動面積集中在特定時段， 且總滑動面積也會因此減少。 關鍵詞：地下水誘發邊坡滑動、自由端、後退型崩塌。 The Characteristics of Dip-Slope Landslides Induced by The Groundwater in Free-End Experiments Su-Chin Chen[1] Kuan-Han Chen[1] Chun-Hung Wu[2]* ABSTRACT Retrogressive sliding can be observed in groundwater-induced landslides. The major inducing factor of this phenomenon is the fluidization in the down-hillslope and the soil of the bottom-layers. Moreover, when the water content in the area around the groundwater input pipe surpasses 29%, sag in the upper soil layer can also occur. As the groundwater discharge increases in experiments with the same slope, the equilibrium time needed to achieve landslide equilibrium gets shorter and the durations of landslides also decrease. As the slope in experiments with the same level of groundwater discharge increases, the equilibrium time required to achieve landslide equilibri- um gets shorter, the landsliding area in a specific time period gets larger and the total landsliding area also decreases. Key Words : Groundwater-induced landslide, free-end, retrogressive sliding. 則可謂為少數特殊案例，經陳聯光等 (2010) 對該起滑動 一、前