Design And Simulation Of Composite Anti-collision Structure Of Single Pile Foundation For Offshore Wind Turbine

With the development and construction of offshore wind farms and the development of maritime shipping industry,the number of offshore wind farms and ships increases sharply,which leads to the increase of the probability of ships colliding with offshore wind farms.If the ship goes out of control and hits the offshore wind turbine,it will lead to the collapse of the offshore wind turbine and the sinking of the ship.Therefore,it is of great significance to improve the impact resistance of the offshore wind turbine.This paper proposes an anti-collision structure for the single pile foundation with weak impact resistance.⑴ The damage failure criterion,the basic theory of collision and the solving process of collision numerical simulation of composite materials are briefly described.Through the simulation of tensile test and tube side impact test of perforated laminates.The effectiveness of Hashin damage failure criterion and the accuracy of collision simulation technology are verified respectively.⑵ The multi-objective optimization design of BCC lattice structure is carried out based on Workbench,and the optimization results are verified.The length,width,height and diameter of BCC cells were taken as design variables,and the maximum stress,strain energy and maximum strain were taken as response variables.After the response surface calculation was completed,the screening method and MOGA method were used to screen out the geometric dimensions of BCC cells most in line with the design requirements.Finally,the low-speed impact response of BCC lattice structure before and after optimization is simulated.By comparing the numerical simulation results,it is proved that the optimized BCC lattice structure has better impact resistance.⑶ The derivation process of the asymptotic homogenization method is introduced in detail,and the asymptotic homogenization method is realized by combining with the finite element software.The effectiveness of the asymptotic homogenization method is verified by numerical simulation of BCC lattice structure compression experiment.Then the asymptotic homogenization method is used to obtain the equivalent modulus of the optimized BCC lattice structure,and the low-speed impact response simulation analysis of the BCC lattice structure and the equivalent model is carried out.The comparison of the simulation results proves the accuracy of the equivalent model.Finally,the low-speed impact response simulation analysis of the BCC lattice cylindrical shell structure and the equivalent model is carried out.It can be deduced from the results that when the radius of the cylinder is large enough,the relative error between the equivalent model and the three-dimensional solid results will be reduced to a critical value.The establishment of the equivalent model greatly reduces the calculation time and maintains the accuracy of the results.⑷ A kind of anti-collision structure composed of rubber,BCC lattice structure and steel is designed for single pile foundation of offshore wind turbine.The low-speed impact response of single pile foundation with and without anti-collision structure protection is simulated by finite element software.The changes of energy,stress,impact force and displacement of single pile foundation in the process of collision under two working conditions are compared.The results show that the anti-collision structure not only has buffering capacity,but also can effectively reduce the damage degree of single pile foundation after collision.