非均匀非平衡输沙数学模型在长江南京以下深水航道整治一期工程中的运用

Application of numerical nonuniform nonequilibrium sediment model in deep water channel phase I project from Nanjing down the Yangtze River

通州沙、白茆沙是长江南京以下12.5 m深水航道上延南京首先碰到的两个重点碍航浅滩,工程河段受径流和潮汐的共同作用,水沙动力复杂,河床冲淤多变。建立三沙河段非均匀非平衡输沙二维潮流泥沙数学模型,在挟沙力公式、底沙与悬沙交换模式等研究的基础上,利用实测水沙及地形资料对模型进行率定和验证。在此基础上,利用该模型对长江南京以下12.5 m深水航道整治一期工程方案进行研究,分析整治工程的效果及影响,为工程设计提供技术支撑。

Tongzhou shoal and Baimao shoal are two major obstacle shoals of the 12.5 m deep water channel extending up to Nanjing in the Yangtze River. The engineering river reach is influenced by both river discharge and tide, hydrodynamics is complicated and river bed is active in siltation and erosion. Two-dimensional numerical tidal model is set up to study nonuniform nonequilibrium sediment movement in the three sand shoals （Fujiang shoal, Tongzhou shoal, Baimao shoal）. Based on the study on the sediment carrying capacity formula and suspended and bed sediment exchange mode, the paper calibrates and verifies the model by measured hydrology and field bathymetry data. The model is applied to the 12.5m deep water channel phase I project to analyze the influence of regulation works and affords technical support for the engineering design.