三峡工程下游宜昌至沙市河段河床冲刷预测

在已建水库下游河床冲刷泥沙数学模型的基础上针对宜昌－沙市河段的河道特性，修改并建立了能够反映该河段水沙运动特性的一维水流泥沙数学模型，在此基础上，进行了三峡建库后，前２０年内宜昌－沙市河段的一维水沙运动及河床冲淤计算。

Prediction of river-bed scouring between Yichang and Shashi at the lower reach of the Three-Gorge Project

Based on the existing sediment mathematical model on the river-bed scouring at the lower reach of the Three-Gorge Project(TGP), an one-dimension mathematical model on the stream load is revised and set up after analysing the characteristics of the the river course from Yichang to Shashi. The revised model reflects the quality of water regime and sand transportation in the corresponding river course. The results given predict the river-bed scouring within 20 years that the Three-Gorge Reservoir is built. In the following ten years after building the Three-Gorge Reservoir, The overburden sand layer on the river bed between Yichang and Shashi will be almost washed away,resulting in a high roughed bed.The undercutting of the garvel and pebble bed will dominate. In the 5th year and later on when the Three-Gorge Reservoir is put into operation, the slope at some local surface of the river-bed beyond Lujiahe will be seen greater, the water level at Shashi dropped more. The more apparent phenomenona will inevitably affects the conditions for shipping.