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標題: 滯洪壩水泥護坦及元鼎塊之消能試驗研究
A Study on the Energy Dissipation of Concret Apron and Hexa- Hollow Tri-Leg Structure of the Flood Detention Dam
作者: Hsiao, Kao-Liang
關鍵字: 滯洪壩;Flood Detention Dam;水泥護坦;元鼎塊;消能;Concret Apron;Hexa-Hollow Tri-Leg Structure;Energy Dissipation
出版社: 水土保持學類
The flow from the rectangular opening of the flood detention
dam will produce scouring and damage on the downstream aprons.
While the water from the rectangular opening flow on the concret
apron, the fan-like flow decentralizes around and scours both
side of the riverbank. The refractive circumfluence produced
from the both side of the riverbank will meet with the flow
without being effected by the riverbank, and both of them form
the turbulent curve. On the downstream of the dam we
place concret apron in the central part and the Hexa-
Hollow Tri-Leg Structure near the riverbank.This
study discusses the effectiveness of energy
dissipation and the effect what the Hexa-Hollow Tri-Leg
Structure does to the turbulent curve under different
slopes,discharges and widths of the rectangular opening in
the case of having not deposited yet on the upstream
of the dam. In this research, we find
that the effectiveness of energy dissipation of
apron will increase with the increasing of slop and
discharge, but will decrease with the increasing of width of the
rectangular opening. According to the type of the Hexa-Hollow
Tri-Leg Structure being arranged,the longer the length of Hexa-
Hollow Tri-Leg Structure is and the better the effectiveness of
energy dissipation is.The length of turbulent curve will
decrease with the increasing of the width of the Hexa-Hollow
Tri-Leg Structure. In this research,we find that the
Hexa-Hollow Tri-Leg Structure being arranged
beside the both riverbank downstream the dam has its
efficiency on shortening the turbulent curve and the
effectiveness of energy dissipation.When applying to the field,
it must be a good choice.

滯洪壩水舌呈豎一字形,勢必對下游護坦產生沖刷與 破壞。且沖射
流作用在水泥護坦上時,其扇形水流向四周 分散,對河床兩岸進行沖擊
,產生折射迴流;並與未受兩 岸邊壁影響之水流交會,形成明顯擾動曲
線。 本試驗於滯洪壩下游,除舖設水泥護坦外,並於兩側
配合人工預鑄元鼎塊之舖設;探討於不同渠床坡度、流量 、矩形開口及
壩未淤滿前之情形下,元鼎塊對擾動曲線之 影響及消能效果。
經試驗得知,護坦的消能效果隨流量,坡度增加而增 加,而隨矩形
開口寬度之增加而減小。就元鼎塊排列方式 而言,在本試驗之元鼎塊長
度範圍下,元鼎塊長度愈長, 消能效果愈差;元鼎塊寬度愈寬,水流所
產生的擾動曲線 長度愈短。
在本試驗條件下,壩下游兩側舖設元鼎塊確有其縮短 擾動區域及消
能的功效;因此在現場應用上,應為一良好 之選擇。
Appears in Collections:水土保持學系

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