Study On Mechanical Characteristics Of Barge-tethering Flexible Positioning Pier Of Floating Docks In Yangtze River And Its Structural Optimization

With the development of ship’s large-scale, the size of the floating dock’s barge isconstantly increasing. The traditional way of berge-tethering such as chains and structsystem can not meet the requirement of large barge positioning. To improve the berthingcapacity of floating berth, using the style of positioning pier to tether the largeberge.Under the circumstance, this paper study on mechanical characteristics ofpositioning pier and its structural optimization. The main contents are as follows:First, combining with the barge-tethering positioning pier of floating dock inYangtze River, Basing on summarized the theory of ship-structure collision in Chinaand abroad, the Minosky theory in the external collision mechanism can be used as themethod of ship-barge-positioning pier system collision to inference the formula of shipeffective impact energy. and then study the relationship between ship impact force andship effective impact when the ship collide different elevations of positioning pier.Secondly, relying on the logistics limited wharf construction project of Wuhu, asimplified numerical model of positioning pier is established by ANSYS finite elementanalysis software.Considering the weight of the structure, wind load, water power, shipimpact force, ship mooring force and ship breasting force, the maximum displacementand internal force in every component of positioning pier is calculated according to themost unfavorable combination of load effects about those loads. The weakest position ofpositioning pier can be analyzed and the force inhomogeneity of front and rear piles ofpositioning pier can be judged according to the position of extreme force of axial force,shear force and moment in every component.Then, combining with the weakest position and the force inhomogeneity of frontand rear piles of positioning pier，the paper supply two kinds of optimization program ofsteel diagonal bracing of positioning pier, the two kinds of optimization include theposition and material of steel diagonal bracing. Which the force inhomogeneity of frontand rear piles of positioning pier be reduced or not by analyzing the different of axialforce, shear force and moment in the same section.Finally, three kinds of optimization which is diameter, spacing and number of pilesoptimization can be proposed based on the material optimization of steel diagonalbracing of positioning pier. Pile top displacement of positioning pier is calculated underthe different diameter and different spacing, and the curve is drawn which is the relationship between pile top displacement and the diameter and spacing of pile.After,the paper discover the best optimization of three piles of positioning pier based on theoptimization of diameter and spacing optimization of steel pile, and then compare theforce uniformity with the three piles and the four piles of positioning pier.