土砂供給の量と質が砂州河道に及ぼす影響に関する基礎的研究

抄録

In many rivers of Japan, bed degradation has been recognized as serious problem which it has caused change of river ecosystems. These days, in some rivers, artificial sediment supply is on trial. However, it is still unknown where supplied sediment deposit, and how and when sediment move. Considering river management, we need grasp detail of sediment movement along river. Generally, estimation of sediment transport along river is treated as one dimensional problem. However, bed form has possibility to affect sediment transport.

We focus on the influences of sediment-supply condition on bed form. In this paper, numerical simulations and trial experiments indicate that sediment-supply condition affect characteristics of bar form from upstream area because of characteristic sediment behavior on bars. And it is clear that change of bar form depends on amount and size of supplied sediment.