Study on Characteristics of Flood Scour and Fill and High Efficient Sediment Transport of the Lower Yellow River

The paper analyzes the characteristics of scour and fill and the process of sediment transport with high efficiency based on the observed flood data of the lower Yellow River.The outcomes show that a) when average flood discharge is greater than 2 000 m3/s,the big or small sediment delivery ratio depends on the average sediment concentration of a flood;b) the relationship between water for sediment transport and sediment delivery ratio is zonal distribution because of different sediment concentration.The flow for sediment transport with the same sediment concentration decreases along with the increase of sediment delivery ratio.When sediment delivery ratio reaches to a certain degree,the flow for sediment transport not reduces remarkably along with the increase of sediment delivery ratio;c) the combination of mean discharge 3 200 m3/s and average sediment concentration 65 kg/m3 can be represent the process of sediment transport flood with high efficiency of the lower Yellow River.