土石流沖淤模式應用於小林村角埔溪災害模擬

The Debris Flow Numerical Model with Erosion and Deposition Effects: An Application in Jiaopu Creek, Hsiaolin Village

曾文孝(Wen-Hsiao Tseng) ； 徐郁超(Yu-Chao Hsu) ； 賴文基(Wen-Chi Lai) ； 詹錢登(Chyan-Deng Jan) ； 謝正倫(Chjeng-Lun Shieh)

《中華水土保持學報》 42卷3期 (2011/09) Pp. 219-227

https://doi.org/10.29417/JCSWC.201109_42(3).0005

摘要

本文利用一以能量守恆觀點推導之土砂運動本構關係理論，建立適用於土石流及高含砂水流之數值模式，並考慮土石流運動過程中，因為濃度變化造成河床的沖刷、淤積效應，以模擬土石流的運動行為。本文以莫拉克颱風期間，小林村的角埔溪土石流為研究案例，將角埔溪的土石流分為兩階段進行模擬，第一階段的目的為評估土石流是否可能造成角埔溪八號橋的破壞。第二階段的模擬是以第一階段模擬成果，配合小林堰塞湖潰決後造成旗山溪河床抬升的地形資料進行計算，以此計算條件模擬所得之成果與實測的地形資料尚屬吻合。

關鍵字

土石流 ； 數值模擬 ； 本構關係 ； 莫拉克颱風

並列摘要

A debris flow model based on the constitutive equation derived from energy conservation and preferable in debris flow and sediment laden flow was developed. The model also considered the erosion and deposition effects contributed by the concentration variation of debris flow. The model was applied to simulate the debris flow disaster that occurred in Jiaopu Creek , Hsiaolin Village during typhoon Morakot. The scenario of the Jiaopu Creek debris flow event was considered in two stages. The primary purpose in the first stage was to see if the elevation of debris flow was enough to bury bridge no. 8. The simulation result and 5m DEM made after the Hsiaolin landslide dam failure were combined as the topographic data in the second stage. The simulation result was comparable to the survey data.

並列關鍵字

debris flow ； constitutive equation ； numerical model ； Typhoon Morakot