关键词: 濛河拓浚工程; 河势影响; 分流比; 河床演变; 非恒定流河网水沙数学模型; 淮河; 王临河段;

Abstract: The Wanglin section is located in the transition area from the upstream mountainous region to the plain in the middle reaches of the Huaihe River, where many tributaries converge into the mainstream and the flood storage areas are frequently used.As a consequence, it is the most complicated river reaches with the highest concern of flood control in the Huaihe River Basin.The planned dredging and extending project in Menghe River will significantly change the main channel scale and the division ratio of main and branch in the section, which may affect the stability of the river regime.Based on the unsteady numerical model of flow and sediment in the river network, the evolution trend of river bed before and after the project is predicted, and the changes of water level and diversion ratio of two branches after the adjustment of erosion and deposition are analyzed.The results show that the current situation of Wanglin section is in a state of slow deposition, the overall deposition amount of river will increase slightly after the implementation of the planning scheme, and the distribution of erosion and deposition along the river will also be adjusted.Under the condition of 30-years water and sediment series, the effect of treatment project can be maintained for a long time, the diversion ratio of the Menghe River has not been further expanded, and there is no unfavorable translocation between main and branch channels.The results can provide a scientific basis for the construction of the project, and have a significance reference for similar projects in Huaihe River.

Key words: dredging and extending project in Menghe River; affection to river regime; diversion ratio; evolution of river bed; unsteady numerical model of flow and sediment in the river network; Huaihe River; Wanglin section;