Study On Collision Mechanism Of Ship And Platform And Optimization Of Platform Crashworthiness

Due to the scarcity of land resources,ocean energy mining continues to increase,and the number of various offshore platforms is increasing.The frequency of collision accidents between ships and offshore platforms is getting higher and higher.Jack up platform is the main offshore mobile platform,as a large offshore jack up platform equipment,large volume,complex structure,high cost,the damage of great impact force generated in the process of impact is very serious,causing great social influence,economic losses and serious secondary disasters.Therefore,it is of great practical significance to analyze the structural damage of collis ion between ships and offshore platforms.According to the research above,firstly,this paper carried on the reliability verification of numerical simulat ion.Simulation of hitting pipes by using t he finite element software ABAQ US and compared results with experimental data,through the comparison of data can be found the simulation results meet the engineering requirements and verify the reliability of numerical simulation.Research on the influence of impact parameters on the damage characteristics of pipes.The bulbous bow of the ship is simplified as a spherical head,and the leg of the offshore platform is simplified into a round pipe component which is fixed at both ends.The influence of the geometric size,impact angle and axia l preload in the damage characteristics of a pipe is studied qualitatively.Three collision case which are under bow,midship and stern collis ion with platform are comparative analyzed.Establish a finite element model o f ship and offshore platform for crash simulation,by comparing the three kinds of displacement time curves and collision scenarios of the collision force time curves and energy curve,the damage characteristics of collision between platform and different part of the ship are analyzed.Research on the influence of the thickness and diameter of the pipes on the W.Analysis the influence of the thickness and diameter of the pipes under the three kinds of collision cases on W in a certain range by using the simplified model,The range of the diameter and thickness of the pipe string under the three cases when the W is small is obtained,and the range of the common optimal solution is obtained by the intersecting of three kinds of collision cases' range.The research on the optimal solut ion of the thickness and diameter of the string pipe under the three collis ion cases.Using the method of multi-objective optimization genetic algorithm,the thickness and diameter of the string pipe impacted as optimization pa rameters,the range of the common optima l solut ion under the three collisoin cases as the optimal range,W as the optimization goal,through iterative get the optima l solut ion under the condition of the three kinds of collision individually.