蛇行流路の形成過程に関する実験的研究

Abstract

The problem of river meandering is one of the main subject on fluvial hydraulics. A lotof researches have been presented on this problem, especially on the planform of meanderingchannel and the initiation of meandering stream. However, fluvial process and mechanics ofmeandering channel formation is not discussed on the basis of experiments in detail.In this paper, we report the results of large scale experiments carried out in order toclarify a process of meander formation and the sediment balance during the process. Theresults of experiments are compared with other experiments, and examined about relationbetween bed load and migration of bars, variation of channel pattern, state of bed load andbank erosion rate of meandering channel and so on. It is obtained that the width relatedwith main stream-thalweg width (= difference between water surface width and pointbar width) or width of sediment transport-is relatively constant and has the same value atthe final state of uniform channel widening. Main stream alignment is also compared withsine-generated-curve", and it seems that the wave length along the main stream, in thisexperiment, tends to have a constant value. At last, the posibility of hydranlic analysis ofmeandering process is discussed.