不同壩高下逆坡消能塊之試驗研究

A Study on the Adverse-Slope Dissipation Blocks with Different Dam Heights

曹正明(Cheng-Ming Tsao) ； 段錦浩(Chin-Hao Tuan)

《中華水土保持學報》 23卷1期 (1992/05) Pp. 63-72

https://doi.org/10.29417/JCSWC.199205_23(1).0005

摘要

現有防砂壩常因護坦或消能塊下方遭受淘刷，進而上溯造成壩體之損壞，故壩下游之消能效果實為影響河床沖刷與壩體安全之重要因素。而逆坡消能塊理論上可消減較多之能量，為一可行之消能措施。本研究針對不同之有效壩高探討逆坡消能塊之消能效果。經試驗發現，消減能量及消能效率皆隨壩高增加而增大，試驗壩高在14公分以上時，消能效率平均可達75％以上。逆坡角度之增加，對消能塊末端之殘餘能量及最大沖刷坑之深度皆有減低之趨勢。在本試驗條件下，各有效壩高之最佳逆坡角度在小流量時均為6.99％（4°），大流量時為10.51％（6°）。

並列摘要

The damage of current check dams is often caused by the advancing up of the scouring at apron or energy dissipation block; herefore, the energy dissipation is one of the most important factors which influence the downstream scouring and the safety of the dam. Theoretically, adverse- slope energy dissipation blocks can dissipate more energy and serve as an alternatives. The purpose of this research is to investigate the energy dissipation effect of adverse- slope energy dissipation block with different effective dam heights. According to the experiments, the total amount and ratio of energy dissipation increase with the dam height increasing; when the dam height is over 14cm, the energy dissipation ratio can go beyond 75% on the average, The increment in the angle of adverse-slope can reduce both the remaining energy on the end of energy dissipation block and the maximun depth of the scouring hole and under the conditions in this research the most advantageous adverse-slope angle in all effective dam heights is 6.99% (4°) and 10.51% (6°) for small and large discharge respectively.