河川의 取入水門設置에 依한 背水現象과 洪水 調節硏究 = Study on the Backwater Curve and Flood Control due to Construction of Intakegate in River Channel

다국어 초록 (Multilingual Abstract)

Backwater curves were first applied to the long, smooth profile of the water surface upstream from a dam or other obstruction in a river channel. There are several methods for determining backwater curves in low-velocity river channels. Each of the methods is based on Bernoullis energy theorem and Mannings friction formula. The most common type of backwater Problems is the determination of water-surface elevations in a river channel upstream a station or Point to which the discharge and water-surface elevation are known. Flood routing identifies the procedure by which a flood discharge hydrograph at any point on the stream is determined from a known discharge hydrograph at some point upstream. It is generally necessary to use approximate flood-routing methods that either ignore some of the factors affecting flood wave movement or are based upon simplifying assumptions in regard to such factors.
Of the many methods for the flood routing or storage analysis, the Muskingum method has mainly been applied to a natural river channel and the Modified Pul's method to a reservoir and weir respectively. In this thesis, Backwater and flood routing problems are analysed jointly.
1. Backwater curves at design water level 2.40m M.S.L. In case of natural river channel, the following theorem was applied
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where Q=192.0 ㎥/Sec, A=300, 7㎡, R=2.65m, n=0.03 as the result, 18cm back water height was derived at the length of 5.3km, (refer to tablee 12).
In case of intakegate established, Bresse formula was applied
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using the above, l=25,015.1-10,000h+??
was derived and 30.2cm of backwater height estimated at the length of 5.3km., In eventual, 2.2cm of backwater height difference between two cases were calculcted.
2. Flood routing at the design storage capacity of 1,964,950㎣(design water level of 2.40m M.S.L.)
Discharge capacity of the Intakegate requires 36mins to drop the height of 2.40 M.S.L. to 0.75m M.S.L. at no rainy condition, and considering 220mm of maximum daily rainfall in flood time, 60mins were required to drop the gage height to the 0.75m M.S.L.
During the control period of 60mins, the water level in each point was followings, Baikgoo: 2,415m M.S.L.(Lowest ground height: 2.52m)
Banwol: 2.67m (2.72m) Masan: 2.60m (3.07m) Dodo: 2.91m (3.28m)
Refering to the above results, a damage may not be met by those backwater curve and flood.