IAHR, founded in 1935, is a worldwide independent member-based organisation of engineers and water specialists working in fields related to the hydro-environmental sciences and their practical application. Activities range from river and maritime hydraulics to water resources development and eco-hydraulics, through to ice engineering, hydroinformatics, and hydraulic machinery.
Log On
About IAHRDirectoryCommitteesMy IAHRNews & JournalseLibraryeShopEventsJoin IAHRWorld CongressDonate
spacer.gif
spacer.gif eLibrary
spacer.gif eLibrary
You are here : eLibrary : IAHR World Congress Proceedings : 32nd Congress - Venice (2007) : THEME A: Engineering and Management of Fresh-water Systems : On river-bed variation mechanism in steep brided channels and a method to calculate inundation dis...
On river-bed variation mechanism in steep brided channels and a method to calculate inundation discharge hydrograph due to dike breach
Author : Fukuoka Shoji, Abe Tomonori
For flood control measures in a steep braided channel, it is important to understand the effect of bed material on the river-bed variation and to estimate inundation discharge hydrograph due to dike breach. In this study we carried out a field experimentation on riverbed variation and dike breach in the floodplain of the Joganji River, which is a very steep braided channel. We investigate the river-bed variation characteristics of low water channel in a steep braided channel and clarify the bed material grain-size group that controls stability of the riverbed. Furthermore, we affirm the role of gain-size distribution and large gravels on riverbed variation by comparing these results with those of field experiments on the Joganji River in 2004. The grain-size distribution of a gravel-bed river's low-water channels can be approximately estimate by measuring grain-size distribution at one location at a minimum and determining D60 for other locations. The authors have developed a computational method for predicting inundation discharge hydrographs with a high degree of accuracy using two-dimensional unsteady-flow analysis in which temporal changes in water surface profile (including at the dike-breach point) are given, but without taking into account temporal change in dike-breach cross-sectional shape, etc. This method was tested in field experimentation simulating a dike breach. The experimental results showed the method to be effective in predicting inundation discharge hydrograph due to dike breach. Furthermore, when used in combination with analysis of river inundation, the method can serve as the technological foundation for a system of predicting inundation with a high degree of accuracy.
File Size : 233,187 bytes
File Type : Adobe Acrobat Document
Chapter : IAHR World Congress Proceedings
Category : 32nd Congress - Venice (2007)
Article : THEME A: Engineering and Management of Fresh-water Systems
Date Published : 01/07/2007
Download Now