河口閉塞に関する二,三の実験

Abstract

When the tractive force of incident waves predominates over that of river flow, theriver mouth is often closed by drifting sand. In order to solve such a problem at theriver mouth, two dimensional tests were performed by using a simple model of the rivermouth.In this paper, as an approach to discover the main factors which influence closingof the river mouth by drifting sand, the effects of wave characteristics, sediment charac-teristics and the river depth on the deposition height and profile of the bar formed at theriver mouth due to wave action are discussed on the basis of some experimental results.It was found that the criterion for generation of the bar formed at the river mouthis determined by the deep water wave steepness, the ratio of the sediment diameter tothe wave height and the ratio of the river depth to the wave height, and that especially, the ratio of the river depth to the wave height is a very significant factor in determiningthe final height of the bar.