設置角度の異なる単独水制周辺の粒度分布変化に関する研究

Abstract

This paper presents an experimental study on the impacts of orientation of a spur-dike on the bed topography and sediment sorting process of bed surface around a single impermeable spur-dike. The importance of one governing parameters, the orientation of the spur-dike, was emphasized through quantitative and qualitative evidences. It was found that each case of the spatial progress patterns of scour-deposition and sediment sorting were different in comparison with different types of orientations. Compared with the deflecting and attracting types of spur-dike, the repelling type has the property of promoting deposition in the wake region of the spur-dike. This property is caused by the difference of flow structure in the vicinity of spur-dike. The coarsened longitudinal region and fine sediment regions were observed, and it was indicated that the repelling type of spur-dike has the strongest intensity of sediment sorting of the three orientations of spur-dikes.