間歇性河道之短期一般沖刷與斜向流基腳最大沖刷估算

Estimation of Short-Term General Scour and Oblique Flow-Induced Maximum Toe-Scour in Intermittent Rivers

郭耀麒(Yao-Chi Kuo) ； 謝天元(Tian-Yuan Shieh)

《農業工程學報》 64卷4期 (2018/12) Pp. 23-43

https://doi.org/10.29974/JTAE.201812_64(4).0002

摘要

臺灣間歇性河川坡陡流急，颱洪時，經常造成河道堤防基腳淘空傾倒，甚而破堤致災。為掌握洪水時的沖刷潛勢，對於河道短期一般沖刷與斜向流基腳最大沖刷在堤防工程設計安全上，為亟需瞭解的課題。本研究於實驗室內建置一代表性擬似斜向流30度攻角之動床彎道流試驗渠槽，經由一系列基本試驗組合，並結合現場案例實測沖刷觀測結果，分別檢定驗證得到2組河道短期一般沖刷經驗式及6組基腳最大沖刷經驗式，經與國內外相關研究做比較，本研究經驗式具有較佳的現場實測估算，可據以提供相關工程規劃設計實務應用。

關鍵字

間歇性河川 ； 短期一般沖刷 ； 斜向流 ； 基腳最大沖刷 ； 動床

並列摘要

For the intermittent rivers with steep in channel slope and rapid in flow velocity in Taiwan, severe streambed scouring, even toe-scour disasters of embankment induced by the typhoon floods occur often. It is an important issue to understand the scour potential of short-term general scour and oblique flow-induced maximum toe-scour for the river flood-prevention and management. In this study, a representative quasi-oblique flow with 30-degree angle movable-bed flume was built in the laboratory. Through a series of basic experiments and combined with field observations of scour-measurement, two sets of short-term general scour and six sets of maximum toe-scour empirical formulas were obtained by verification. Compared with domestic and foreign research, this research's empirical formula has a better scour estimation, and can provide for practical applications of relevant engineering planning and design.

並列關鍵字

Intermittent rivers ； Short-term general scour ； Oblique flow ； Maximum toescour ； Movable-bed