土石流之基礎研究（I）土石流發生機制之研究

Basic Study on the Debris Flow (1) Study on the Mechanism of the Occurrence of Debris Flow

游繁結(Fan-Chieh Yu)

《中華水土保持學報》 18卷2期 (1987/11) Pp. 28-40

https://doi.org/10.29417/JCSWC.198711_18(2).0003

摘要

爲瞭解土石流發生之機制，本試驗以自然土砂礫，均匀礫石及粗砂等三種試料，模擬土石流之發生，以掌握其誘因，並驗證所推導之理論公式，而得如下結果。（1）依滲流理論考慮渗流力與間隙水壓之作用下，可推導土石流發生之臨界條件爲（方程式略）（2）由試驗證明該公式可有效推估土石流發生之可能性。（3）斜面上堆積土砂礫之組成與土石流之發生有關，土體中含適量之礫石，高孔隙率及大孔隙之存在，均爲導致土石流發生之基本條件。（4）本試驗所推導之理論公式，似可作爲土石流防治之工程設計依據。

關鍵字

土石流 ； 機制 ； 滲流力 ； 發生流動

並列摘要

To realize the mechanism of the occurrence of debris flow, three kinds of materials, natural deposits sampled from Fong Chiu, single-grained gravels and coarse sands, were used to simulate the occurrence of debris flow in flume. Meanwhile, the caused factors of debris flow were investigated and the theoritical equation of its occurrence was derived in this experiment. And the results were obtained as follows: 1. The occurrence of debris flow could be derived as following equation under considering the seepage force and pore water pressure. (The equation is abbreviated) 2. This equation was proved that it could be effectively applied to forecast the possibility of the occurrence of debris flow in this experiment. 3. The natural deposits which contain some amounts of gravels with high porosity and vast pore size, were easily caused to become debris flow on steep slope. 4. The derived equation could be applied to design the height and the depositing slope of check dam which was going to prevent from the occurrence of debris flow.

並列關鍵字

Debris flow ； Mechanism seepoge force ； Occurrence ； flow