利根川下流部における河川改修の効果算定法に関する研究

抄録

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.