THE EFEECTIVENESS OF THE RIVER IMPROVEMENTS IN THE LOWER TONE RIVER

Naoki IWAYA, Shoji FUKUOKA and Hidenori ZENIYA

In the Lower Tone River, channel dredging and widening have been conducted to respond to the large floods. However, the current river channel has still insufficient capacity for the present design flood. So, it is required the appropriate river improvement works in the future, and therefore it is important to clarify the changes in cross-sections and effectiveness of the past river improvement works. We investigated changes in the characteristics of channel shape resulting from the channel widening by using non-dimensional plan shape parameters. The result provided that there was little difference of characteristics of plan shape between the natural meandering channel and the Lower Tone River after river improvement works in spite of conducting the channel widening. Furthermore, we suggested the effectiveness of the river improvement works in the Lower Tone River by using Fukuoka’s equation.

Key Words : the Lower Tone River, river improvement works, channel widening and dredging, flood flow, channel shape, Fukuoka’s equation

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1)

B1

Vol.69 No.4 I_1003-1008 2013

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B1 Vol.68 No.4 I_1135-1140 2012

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No.754/ -66 pp.19-

31 2004

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B1

Vol.68 No.4 I_1423-1428 2012

5) 1987

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