Research For Mooring Ship Movement, Mooring Line Forces And Impact Eenergy Of Open Terminal

Taking into account open terminal located in the open water where the condition of wind wave and current is complex, the docking condition is difficult to research by gerneral theory. But ship operation and port safe production is related to docking condition so that its in-depth study plays a significant role in practical project.The paper deals with ship movement, mooring line foces, impact energy under irregular waves and current through theoretical analysis and model test.Under the wave action, ship moves to six degrees of freedom. The ship stand-off from the terminal, resulting in considerable force in the mooring line; the ship pushs against the terminal, resulting in impact energy. So study for the ship movement is the preparation for other research. According to the equation of ship movement, analytical solution is calculated which provides the elements related to the ship movement. And then analyze the regular pattern of ship movement changing with the elements, empirical formula is presented.Mooring line forces is produced by the ship movement which makes the lines stretched. In accordance with the same method, the regular pattern of mooring line forces changing with every element is analyzed by model test, and empirical formula is presented.Ship impact energy depends on ship characteristics and movemet, through the analysis of the model test, the regular pattern of impact energy changing by elements is given on the basis of which empirical formula is presented.Except waves action, ship is also affected by current action. The different current direction and velocity makes the different function. In general, when the current pushes the ship to the terminal, the ship squeeze the terminal, when in the opposite direction, mooring line forces produce. Through analysis of model test, the regular pattern of squeezing forces and mooring line forces are given.In detailed study of docking condition under wave and current action, two examples of projects are cited to verify the pattern and formula. Research conclution is given at last.