Structure Design And Characteristic Research For 7MW Offshore Wind Turbine Pile Foundation

In recent decades,countries around the world have been vigorously developing marine wind energy resources.As one of the offshore wind turbine foundation structures,the high-rise pile cap foundation structure is still in the stage of research and development because of its complex stress in the harsh marine environment for a long time.Due to many uncertain factors,such as material characteristics,external load,structure shape and size,etc.need to be considered in the design process of this kind of structure,the research on this structure is still in the development stage.In addition,there i5 no uniform design specifieation for this type of structure in China,so it is of great significance to study the mechanical characteristics of this type of structUre.The mian research contents of this paper are as follows:Based on a 7MW offshore wind turbine project,according to the design data such as hydrology,geology,and superstructure loads,and referencing the existing engineering experience in relevant fields,the design of the foundation structure of the offshore wind turbine rise pile cap is completed.The soil plastic constitutive model,nonlinear contact theory,dynamic equilibrium,damping calculation theory,wave force calculation theory,and m method calculation theory are discussed.The three-dimensional numerical model of the structure is established and the rationality of the numerical model is verified.Based on the three-dimensional numerical model,the static load response of the structure under different working conditions is analyzed.The results show that the material strength,displacement,and settlement of the high-rise pile cap foundation designed under various working conditions can meet the requirements,and the structure is safe and reliable.Study the force characteristics of the structure under the condition that a load acts alone and different combined loads,.The results show that the wind turbine load and wave force,which are mainly horizontal forces,have a great influence on the structure,which is the main factor that affects the structural stability.In addition,the influence of anchoring ribs with different elastic modulus and anchoring length on the structure is studied by using the method of controlling variables.The load response of the structure under the action of seismic waves is studied by taking into account such factors as the intensity of seismic waves,the types of seismic waves,the change of water level and the type of wind turbine load.The time history of acceleration and displacement of the apex of the cap and the pile,the stress distribution of the main components of the structure,the displacement distribution along the pile body,etc are obtained.It provides a certain reference for the aseismic design of similar projects.