Design And Research Of Pile-style Foundation Structures For Offshore Wind Turbine

Maritime wind energy,as a kind of abundant renewable clean energy,its popularization and application has already become the tendency.The complexity of wind turbine foundation in hostile environments leads to the high cost of the offshore wind power.In the absence of norms,intensity,stability and fatigue life of the wind turbine foundation is studied and analysed in this paper.Based on the results of lectotype optimization,wind turbine four-pile foundation is choosed for analysed.The study includes environmental load,the structure of static and dynamic calculation,fatigue analysis.(1)The environmental load includes seismic load,wave and current load.Fifth-order Stokes wave theory is used for static calculation.Wave spectrum with Wen shengchang method is adopted in dynamic analysis.Calculation result shows that horizontal wave force is bigger than the load of wind turbine.(2)ANSYS software is used in static calculation.Member of wind turbine foundation is simulated as pipel6 unit.Sixfold-pile diameter method,m-method and p-y curve method are used for simulated and compared in pile-soil interaction analyses.The result of p-y curve method is biggest.It can be used in the absence of measured data.(3)In order to ensure the normal operation of wind turbine,dynamic analysis needs to be discussed.The result of modal analysis shows that the top ten steps of the natural frequencies are between 0.35Hz and 4.5Hz,and the first step is 0.352Hz.Environmental and structural loads are able to avoid resonance in the analysis of Harmonic response.It's found that the structure is stable under the force of ether wave and earthquake spectrum or wave and earthquake time-history.4)As the cyclic loading of wind turbine foundation,it is necessary to analyse the fatigue life of the structure.Through the further optimization for the structure,shell93 element is used in this paper to do fatigue analysis of the stress concentration.The design and calculation process of the wind turbine foundation is discussed in this thesis.It has reference value for the similar problems.