Research For Strength Of Jacket Offshore Wind Turbine Steel Support Structure And Grouted Connections

Under extreme environmental loads such as wind,waves and current,offshore wind turbine tends to break down after years of working.The supporting structures of wind turbines could be divided as steel and grout by material,and there are many differences between these two materials.It is indispensable to analyze the strength especially fatigue strength dividually,after the design of supporting structure finished.In this paper,jacket offshore wind turbine is used as an example,to study force characteristics of steel structure and grouted connections respectively,as well as their fatigue features.The main contents are as follows:1.The theory of wind load and wave load are introduced firstly.Wind load is mainly related to momentum theory and Blade Element Theory,while wave load involves the calculation of deterministic wave and random wave.2.Mechanical properties of steel supporting structure and grouted connections are studied.Firstly the actual working conditions are modeled,then considering environmental loads,using finite element method,the forces on them are analyzed.3.Fatigue analysis of tube joints in steel supporting structures of jacket offshore wind turbines is conducted.By using the software of ANSYS,fatigue damage of the tube joints under wind loads and wave loads are resolved separately,the values of which are then superposed to evaluate their fatigue performance.4.Lastly,the material of grouted connections is assessed about its fatigue feature.The effectiveness of calculating its fatigue life is discussed.