Fundamental study on characteristics of sediment movement at the bed surface layer composed of sediment mixture

目前，二维水深平均水流和河床变化的数值模拟将有助于河流管理。 然而，由于在预测真实的河流中的泥沙行为方面存在问题，因此很难详细检查表面的泥沙条件或底质结构。 此外，混合泥沙输运的属性因物理条件而异，因此难以用数值模拟来描述。 为此，首先进行了两组水槽试验，以研究两种粒径泥沙的床面泥沙运动规律。 这些试验和一些模拟结果表明，细、粗泥沙运动特性对泥沙运动数学预报具有重要意义。

These days, 2-dimentional numerical simulation of depth-averaged flow and bed variation would be useful for river management. However, it is difficult to examine either sediment conditions at the surface or the substrate structure in detail because of problems in predicting sediment behavior in a real river. Furthermore, the attributes of mixed sediment transport vary depending on physical conditions, making it difficult to describe using numerical simulations. Therefore, two series of flume experiments were firstly conducted in order to examine sediment behavior through bed composed of two size of sand. These experiments and some simulation results indicated the important characteristics of fine and coarse sediment movement for prediction of math of sediment transport.