Ultimate Strength of 10 MW Wind Turbine Tower Considering Opening, Stiffener, and Initial Imperfection
This paper evaluates the effects of door opening, collar stiffener, and initial imperfection on the ultimate strength of a 10 MW wind tower. The lower segment of the tower was modeled to investigate the ultimate strength using steel cylindrical shell elements of finite element program ABAQUS. The wind tower was classified into three categories; without opening nor stiffener (C1), with opening but no stiffener (C2), and with opening and stiffener (C3). The C2 and C3 were further divided into long axis and short axis categories depending on the position of the opening. Result from linear and nonlinear analyses shows that the bigger the opening the bigger the reduction in strength and the same thing goes for the initial imperfection ratio or ovality of the shell. Also, there is a significant decreased in strength as the initial imperfection ratio increases by as high as 18.08%.
KeywordsWind tower Opening Stiffeners Ovality of shells Finite element analysis
This study is funded by Ministry of Land, Transportation and Maritime Affairs of the Korean Government through the Construction Technology Innovation Program (Grant Code 12 Technology Innovation E09) and Technology Advancement Research Program (17CTAP-C132629-01).
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