- 期刊
推移載輸沙模式之通式化研究
General Formula of Bed Load Functions for Sediment Transportation
摘要
台灣全島年平均降雨量高於2,500㎜，當颱洪豪雨時，洪流夾帶大量泥沙，産生河道沖淤、河道變遷問題，進而造成水工結構物及跨河構造物遭受破壤，河川總輸沙量中之推移載，為其影響重要因素之一。由1879年Du Boys提出推移載運勤曳引力理論後，有關推移載之半經驗模式與推估方法相繼提出，本研究集54家60式，以河床Manning粗糙度n、平均流速U、泥沙粒徑D及水流深度d等四種基本水力因子爲參數，提出一推移載輸沙量q(下標 bw)之通式爲(方程式略)。經各家公式之分析比較，獲致以α=3、β=4、γ=0~1及δ=0.5~1之架構者島最多，若以α=3、β=4、γ=0.5及δ=0.5或α=3、β=4、γ=0及δ=1之組合，則與因次分析所得結果相符合。
並列摘要
In average there is more than 2,500 millimeters precipitation in Taiwan annually. During the period of typhoon and heavy rainfalls, stream flows usually carry a lot of silt through the rivers and destroy the hydraulic structures. The bed load of sediment transportation is the key cause. After Du Boys (1879) initiated the concept of the tractive force to analyze the bed-load discharge, numerous bed-load formulas have been proposed. This study uses hydraulic parameters as bases such as Manning roughness n, average velocity U, sediment size D, flow depth d, a bed-load transport formula is proposed and can be written as (The equation is abbreviated). After comparing the existing bed-load transport equations, the results indicate that the most commonly-used values for (α, β, γ, δ) is (3, 4, 0-1, 0.5-1). The values are similar to the results of dimension analysis of (3, 4, 0.5, 0.5) or (3, 4, 0, 1).