Predict The Variation Of Hydrodynamics And The Evolution Of Seabed Under The Condition Of Developing The Yangshan Port Engineering

At present our country coastline resources are severely scarce, we will alter the developing target to the island coastline of the comprehensive utilization. But there has different between the island coastline and the coastline is next to land:First, the islands boundaries affect the environment of hydrodynamics, the rules of Spatio-temporal changes are complicated; Second, because of the environment of hydrodynamics is changed, the rules of the seabed evolution will be change, and this is not same with the nearshore; Third, various kinds engineering construction would change the boundary, the environment of hydrodynamics and the seabed. To develop the island coastline reasonably and efficiently, remit the contradiction between the requirement of coastline and the shortage of coastline, study on the island coastline is very important. The rules of sediment movement is critical.Study on the sediment movement of the seabed in the archipelago waters, adopt the numerical simulation, study large scope, less expense, short time limit are its feature, with the prototype observation material or modeling material, we can obtain reliable result.The 2-D flow-sediment mathematical model includes hydrodynamics model, computing the suspended sediment model, the seabed transformation model; when the hydrodynamics model is good, then adopt the numerical calculation, then quantitatively discuss the influencing level to the suspended sediment concentration by each parameter, find the best value of the main parameters; confirm the 2-D sediment mathematical model. Direct at developing The Yangshan Port Engineering, there has two plans, adopt the good 2-D flow-sediment mathematical mode, compute the hydrodynamics and the evolution of Seabed. The results show:(1) The paper establish a 2-D flow-sediment mathematical model, the model can reappear the characteristics of the current and the rules of the seabed evolution; so we could use it to compute the hydrodynamics, sediment motion, predict the seabed evolution in the Yangshan port.(2) Under the condition of the muddy seabed, with the tide as main outside dynamic to the sediment movement, the value of bed roughness, dry density of the bed layers, sediment transition between layers affects the suspended sediment concentration, Research shows that, the best value for bed roughness of 2d, for the soft bed layer of 250kg/m3, for the sediment transition between layers of 0.001kg/m2/s. By using the value of parameters to calculate the suspended sediment concentration of Yangshan Port, the suspended sediment concentration and the measured data are coincident.(3) Develop the Dayangshan port can improve the current and sediment of the Yangshan port, the mature development condition is good, so it offer the better coast dynamics to develop the Yangshan port.(4) Provide two plans of the I development in the Dayangshan port. From the point of improving the current and sediment motion, the Datongdao plan is good.