| This paper analysis the practical conditions, layout styles, and problems of the adjacent harbors, and presents the necessity of the construction for the North Yangshan harbor. It firstly summarizes and introduces the theory of "Water constricted by island effect", then, based on this theory, brings forward a method that can found a sea-gate-extended quay wharf which has two bell mouths at each end in the longitude, and a narrow passage in the middle". This theory and method is studied and verified by the numerical tide-model, and has the advantage of a long and straight coast, wide harbor basin, and it could also maintain a large velocity in the basin and could reduce the resedimentation. In the long run, if a deeper water depth is needed, it can be obtained by the adjusting of the length and width of the entrance to accommodate the velocity in the harbor basin and the tidal prism. We can also found extensions in the lateral to form harbors which consist of many parallel man-made islands. This paper also introduces the integrated layout of Yangshan harbor, which is the pioneer in the academic domain, using the northern coast of the small Yangshan harbor, assisting by the above theory, to construct a man-made island 2 kilometers aside, this island can also play a role of the seawall, so a "sea gate" is formed, which has bell mouths at each end, and a channel in the width of 1.6-2 kilometers in the middle, this sea-gate can constrict water, as a result, the sediment carrying power is maintained or even exceeds the natural condition, avoiding the resedimentation, and finally forms the layout which is: a southern harbor block 10 kilometers in the south,, a northern harbor block 10 kilometers in the north, and an interior water area in the middle which has a water depth of about 16-18 meters. This layout-plan increases the deep-water shoreline resources for the international navigation center in Shanghai , and provides room for the Yangshan deep water harbor, which is of great meanings. |
