Application Research Of Two-dimensional Water And Sand Model Based On Digital Channel In Navigation Maintenance Decision

The Digital Waterway realizes the digitization and standardization of nautical chart, as well as the informatizationand interconnection of navigation facilities such as navigation marks. However, the researches on waterway evolution and decision-making based on Digital Waterway are still in early stages. In this paper, we studied the application of flow-sediment modelfor waterway maintenance based on the Digital Waterway, from the aspects of data mining and exchange, flow-sediment model building and predicting the changes of the waterway siltation and erosion. The main contributionsof this paper are as follows:1. The theoretical data model, data structure and encapsulation analysis method of S-57 format electronic channel chart are analyzed. The method of data extraction and coordination transformation of CAD channel chart and electronic channel chartare studied. The extraction method of water depth data, which meet the requirement of 2D flow-sedimentmodel, fromS-57 format electronic channel chart is realized. The data exchange issue of Digital Waterway and mathematical model is also solved in this paper.2. The Heishazhou waterway is selected as theexperimental region, and the 2D flow-sedimentmodel is established based on the Digital Waterway. Both daily average discharge process and sediment process data from Datong station are chosen as the inlet boundary conditions. Considering the lack of Gaoanpolder's water level boundary data, one-dimensional unsteady flow model HEC-RAS is used to calculatewater-surface line from Wuhu water level to Gaoanpolder.3. The terrain data of the verified 2D flow-sedimentmodel is updated based upon electronic channel chart data. After inputting the predicted hydrological conditions, themodel predicts the sediment scour and deposition of the experimental river reach. And the predicted results can be used on the waterway preventivemaintenance and management work. This model realizes the water-depthsurveying task scheduling based on the prediction of scour and deposition range, waterway dredging on low water season and dynamic management of navigation marks.In conclusion, the 2D flow-sedimentmodel based on mining the prolific data source from Digital Waterway can be used on decision making and preventivemaintenance, which improves the qualityand efficiency of waterway maintenance.