Research And Analysis Of Capability Of Structure Of Offshore Wind Turbine

The design of structural of offshore wind turbine is a major component of the whole design and it is a complex and systematic project. It relate to many aspects , such as the marine environment, marine structures design, offshore pile foundation engineering, the interaction of foundation and ground. The design and research of the structural of offshore wind turbine is still in the initial stage in our country, The studies of the limit load under the action of wind and wave forces, tower dynamic response, etc. are almost a blank.In this thesis, our main research object is 1.5MW single pile offshore wind turbine, Through analyzing single pile under horizontal load bearing performance and Comparing current available calculation method of horizontal bearing capacity of pile foundation, we prove that p-y curve method is most suitable calculation method for the horizontal bearing capacity of pile of offshore wind turbine.Aiming at the study of main load of offshore wind turbine, including wind, waves, currents,and ice load.,We established the load calculation system of offshore wind power structures in this thesis. Building the overall model of structure of offshore wind turbine with the finite element software ANSYS, through large amount of calculation, we gave the response of offshore wind turbine structures under the conditions of normal operating, the limit waves and limit ice and checked the strength and stability of of structures. By modal analysis and transient dynamic time-history analysis under the conditions of limit wave, we study the vibration characteristics of the various bands of the platform, characteristics of dynamic response and dynamic amplification effect, finally the necessity of dynamic analysis for the structure of the offshore wind turbine is also verified. Combined with the acutal data of soil, we analyzed the effect of liquefaction soil for foundation bearing capacity, modified the existing p-y curves by adding double cofficient, and then calculated the horizontal bearing capacity for sand layer while liquefation. After that, we proved that liquefaction of soil have big influence on displacement of the pile on the mud line by utilizing finite element analogy.Our achievement is providing certain theoratical basis for rational design of the structure of offshore wind turbine, bringing certain practical value into the development of China's offshore wind power industry. The research on Offshore wind turbine structure can provide reference for future optimization design of Offshore wind turbine.