Model Test Study On Motion And Dynamic Response And Optimization Of Berth In Open Water Area

In recent years, with the development of China's rapid economy, the throughput of ports increases substantially, the scale of port construction expands rapidly, meanwhile, it shows some new features: ship becomes larger, berths becomes deeper, the pier structures become more novel. Because of wind, wave, current and other natural conditions in open water area, whose size and direction reveal the complex phenomenon of strong randomness, motion and dynamic response of the ship is more complex under the action of the external environment loads, so this brings special problems in dock design.Through 3-D irregular wave and current experiment in the wave basin, based on the condition of a 200,000 and 300,000DWT ship(empty load, half load, full load),the ship movement, mooring lines force ,and impact energy of a moored ship under the action of the single wave(wave height:0.5m-2.5m,wave period:7s-15s) and single current (current direction: 0°-±15°,velocity of current: 0.5m/s-2.5m/s), and under that of the combined wave and current (wave height: 0.5m- 2.5 m, wave period:7s-15s; current direction: 0°-±15°, velocity of current: 0.5m/s-2.5m/s)are tested in the model, and the results are analyzed and summarized, the impact is studied of the ship load, length of berth, the direction of rope, wave direction, wave period, wave height, current velocity, and flow direction to mooring force ,ship movement and impact energy, the axis of the berth is optimized under the effect of the complex current, meanwhile, the lengths of island berth, calculated through Chinese Technical Code and OCIMF's Mooring Equipment Guidelines and BS 6349 Maritime Structures, respectively, are optimized. It is of some reference value for engineering design and code amendment.The goal of the paper is to propose semi-theoretical semi-empirical formula of the mooring force ,ship movement and impact energy under the action of the combined wave and current ,it is of some reference value for wharf design and code amendment, meanwhile, according to the characteristics of natural conditions of open water area, the basic principle is provided for the moored ship at berth with the best conditions (the smallest cable tension and the smallest amount of displacement), Through systematic study ,the method to definite the the axis of the berth and the length of island berth is proposed. In the paper , mooring systems is optimized, and the principles and methods are proposed for design of the pier, accordingly, it play an important role in safety of the moored ship and improvement of the efficiency of terminal operations in Similar projects.