Investigation On Analytical Deduction, Numerical Simulation And Model Test Verification Of Jacket Platform Tubular Member Impacted By Wedge Head Scenario

Jacket platform has become the main structure of the offshore platform.With the rapid development of the world's shipping industry,the number of ships sailing at sea is increasing,loading tonnage is increasing.When jacket platform works in exploration and development of marine resources,the possibility of suffering collision from supply ships and other tankers rises rapidly.In the event of a collision,the circular column can be seriously plastic-deformed by the impact of external loads,which greatly reduces the structural strength and load-carrying capacity of the jacket platform.In severe cases,the overturning of the platform will not only cause a huge economic losses and casualties,but also result in a huge marine ecological environment disaster.Therefore,it is important to assess the crashworthiness of the jacket platform during the stage of jacket platform design.In this paper,the deformation mode and impact force of the circular column of jacket platform impacted by wedge head are studied by using analytical method,model test and numerical simulation.Based on the theory of plastic mechanics,a method to calculate the impact force of a circular column impacted by wedge head is proposed.The model test and numerical simulation are used to analyze the deformation of the circular column.The reliability of analytical method is verified.In addition,scenario of the tubular member impacted by bulbous head is studied through experiment and numerical simulation.The details are as follows:1.The development of crashworthiness study of jacket platform is summarized.Based on the model test and numerical simulation,the deformation mode of the circular column impacted by wedge head is improved,an analytical method to estimate the circular column impact force is put forward by using the plastic mechanics principle based on the new deformation mode.2.Through model test and the nonlinear finite element method,the scenario of rigidly fixed tubular member impacted by wedge head is simulated.The results obtained are compared with those of the analytical method,which verifies the accuracy of the analytical method.3.Model test and numerical simulation are used to simulate the scenario of tubular member impacted by bulbous head.The deformation mode and the structural response of the tubular members are analyzed.By building a complete finite element model of jacket platform and simulating the scenario of collision by bulbous head,the influence of the elastic response of the jacket platform on the plastic deformation of the damaged tubular member is studied.The results of this study can be used to estimate the impact force of the tubular members impacted by wedge head.The deformation model and structural response of tubular member impacted by bulbous head are predicted.The crashworthiness of the entire jacket platform is also studied.The research results can be used in the design of the jacket platform and the rapid assessment of structural damage of the jacket platform after the collision accident.