豐丘土石流發生臨界降雨線之研究

The Critical Rainfall Line of Debris Flow Occurrence at Feng-Chiou

范正成(Jen-Chen Fan) ； 吳明峰(Min-Fon Wu) ； 彭光宗(Guang-Tzung Peng)

《地工技術》 74期 (1999/08) Pp. 39-46

https://doi.org/10.30140/SG.199908.0003

摘要

本文以豐丘土石流為案例，研究一級溪流土石流發生臨界降雨線之設定方法，其中包括新方法之提出，及其與傳統方法之比較。土石流發生臨界降雨線為預警系統警報發佈之重要依據，傳統的研究藉由有效降雨強度及有效累積降雨量之關係，設定大面積流域之臨界降雨線；本研究則針對一級溪流預警系統之需要，考慮洪水消退係數之影響，建立有效累積降雨量及降雨延時之關係，探討豐丘地區土石流發生臨界降雨線之設定方法，以期能為一級溪流土石流預警基準提供較佳之依據。

關鍵字

土石流 ； 臨界降雨線 ； 洪水消退係數

並列摘要

In this study, Feng-Chiou was selected as a site to investigate the methods for establishing the critical rainfall line of debris flow occurrence of first order streams. The methods presented in this study consisted of the proposed method and the conventional methods. These methods were also compared in this study.The critical rainfall line of the debris flow occurrence is the foundation of the warning system of debris flow. In the conventional method, the critical rainfall line is determined by using the relationship between effective rainfall intensity and effective cumulative rainfall amount, which is applied on large area basins. In the proposed method, the critical rainfall line is determined by using the relationship between effective cumulative rainfall amount and duration, which can be applied on first order streams. In the proposed method, recession coefficient is considered. Using the proposed method, Feng-Chiou was selected as a site and the critical rainfall line of debris flow occurrence of the site was then established. The new method is expected to be a better basis for the warning system of the debris flow of first order streams.

並列關鍵字

Debris flow ； Critical Rainfall Line ； Flood Recession Coefficient