Effects Of The Hydrodynamic Conditions Of Zhanjiang Bay Reclamation Project And Prediction Of Its Silt Sedimentation

Filling sea for land is of significant importance to the development of human society. It is an effective means to mitigate the contradiction between supply and demand of land in the coastal areas, and to expend the space of living and social development. It has tremendous social and economic efficiency. But filling sea for land will produce impacts on the hydrodynamic conditions, silt movement pattern, and ecological environment of the off-coast area. For years the change of silt movement characteristic, sedimentation problems, as well as their influence on port and channel increasingly draw the public's attention. So, it is very important to rationally develop and comprehensively use the coastal resources, and to optimize the coast line in marine reclamation.According to Zhanjiang Bay coast line and port area planning, the water and land area of the Baoman Port and the nearby industrial village is broad. Its geological and water-depth conditions are good. And Sea coast line is stable with good conditions for shipment. For this reason a plan for filling sea for land is being made here. It will become an excellent area for development of modern logistics and for construction of container pier.Using the ripe 2D full hydrodynamic border treatment model, through numerical simulation to obtain data of the flood rapidness, high tide, ebb rapidness and low tide flow field of the tide cycle of the first and second plans before the project construction and through analyzing the effect of the two plans of the marine reclamation project on the hydrodynamic conditions of Zhanjiang Bay, this article points out the advantages and disadvantages of the two sea filling projects under the hydrodynamic conditions. Secondly using the obtained hydrodynamic field to set up silt mathematical model (when applying Dou Guoren's formula of flow sediment-laden force, introduce the Shields starting conditions of sediment) and through numerical simulation to obtain sediment distribution in the sea-bed of the first and second plans before project construction to compare and analyze the sediment distribution pattern of the bay before and after sea filling, and its effect on port and channel, this paper lists out the advantages and disadvantages of the two plans of marine reclamation. Finally, through comprehensively evaluating the interference and sedimentation conditions of the bay environment caused by the marine reclamation, the paper puts forward an optimized coast line for marine reclamation construction.In the model, the finite volume method discrete of power function is adopted for the hydrodynamic and silt diffusion equations. Finite volume method is a method of using integral to solve differential equation. Its essential is to divide the calculating zone into several non-overlap controllers. In each controller, the model equation is differentiated to get a group of diffusion equations. Diffusion equation belongs to implicit equation which can be solved by using the rectangular and alternating lattice, and by SIMPLER calculating method.