Study on the Riverbed Evolution under the Condition of Clear Water Flushing

Abstract

Water flow downstream of the hub is clear, and the riverbed scouring is large, which affects the navigation depth of the channel. In this paper, the flume experiment is carried out to study the degree of undercut of the riverbed under the action of clear water scouring, the change of the particle size of the bed load, the decrease of the water level and the change of the sediment transport rate along the channel. The results show that the initial channel of the lower reaches of the hub is eroded. With the deepening of the riverbed, the bed material is coarsened and the erosion is gradually weakened, and the later flushing rate is gradually constant. The inlet water level in the sanding section first drops steadily and then gradually stabilizes. The water transport rate along the channel is a power function relationship with time. In the power function relationship, there is a balanced sediment transport period.