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http://dx.doi.org/10.3741/JKWRA.2013.46.9.909

Experimental Analysis of the Morphological Changes of the Vegetated Channels  

Jang, Chang-Lae (Dept. of Civil Engineering, Korea National University of Transportation)
Publication Information
Journal of Korea Water Resources Association / v.46, no.9, 2013 , pp. 909-919 More about this Journal
Abstract
This study examines the hydraulic characteristics, the channel changes, the behavior of bars, and bank stability by means of laboratory experiments. Three sets of laboratory experiments are conducted to elucidate the influence of riparian vegetation of the channels with erodible banks. Flow velocity is decreased in the vegetated zone, the mobility of lower channels is decreased. The double Fourier analysis of the bed waves shows that 1-1 mode (alternate bar) is dominant at the initial stage of the channel development. As time increases, 2-2 and 2-3 modes (central or multiple bars) are dominant due to the increased width to depth ratio. As the vegetation density is increased, the number of bars are increased, bank stability increases. The variation of sediment discharges is affected by vegetation density. The braided intensity is decreased with vegetation density. As the vegetation density is increased, the correlation coefficient of bed topography and bed relief index is increased.
Keywords
laboratory experiment; riparian vegetation; morphological changes; bars; double fourier analysis;
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Times Cited By KSCI : 2  (Citation Analysis)
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