緩坡上石流運動之研究
Other Title
GRANULAR FLOWS ON MILD INCLINES
Journal
中華水土保持學報
Journal Volume
24
Journal Issue
1
Start Page
1
End Page
11
ISSN
0255-6073
Date Issued
1993-05
Author(s)
Abstract
臺灣東部山坡地之土石流現象主要爲石流（granular flows）。本文利用Savage and Hutter在1989年提出之石流運動方程式以特徵線法（method of characteristics）來研究石流運動之行爲。我們發現：當石流總質量大，土壓係數大，或坡度陡時，石流較易運動，運動後速度較大，停止後波高較小，最後傳遞距離較遠。另外我們也以數值方法來模擬擋土牆的影響。結果發現在不考慮擋土牆側之靜壓力時撞擊力先爲負後爲正，最後則爲很小的靜壓差，因爲震波太弱，故最大撞擊力主要來自動能。撞擊力與擋土牆距離之關係則是先增後減，在石流前端速度最大時，有最大撞擊力。而最大總力則爲最後靜壓，並與擋土牆之距離成反比。
Granular flows occur frequently in the mountainous area of east Taiwan. We use the model proposed by Savage and Hutter (1989) to simulate the motion of granular flows. As the total mass, earth pressure coefficient or bottom slope increases, granular flows can start moving easier. As a result, the maximum velocity increases, the final wave high decreases and propagation distance increases. The impact force on a structure first increases then decreases in time. The front shock wave is too weak to contribute. The most important impact force comes from the kinetic energy. Impact force first increases to a maximum then decreases as the position of the structure moves downstream. But total force decreases as the structure moves doconstream.
Subjects
石流
特徵線法
震波
Granular Flows
Method of Characteristics
Shock Waves
Type
journal article