In order to consider shear effect influence of the prefabricated concrete tower for segmented wind turbine
a formula for calculating the warping shear coefficient of one segment with arbitrary geometric dimensions is derived. The finite element models of concrete towers with 2-6 segments are established to compare the twist angles of numerical analyses
the code’s method
the warping shear formula
and the Vlasov theory
respectively. The results show that the warping shear coefficient is negatively related to the center angle of the segment and positively related to the ratio of thickness to radius. The shear effect of the tube with fewer segments or a smaller ratio of thickness to radius is more significant. The code’s method and the Vlasov theory will greatly underestimate the torsional deformation of the segment. In certain cases
it will be only 52% and 21% of the numerical results. The proposed method considering the warping shear coefficient is not only safer
but also generally consistent with the numerical results. The deviation can be reduced by more than 30% than the code’s method under specific cases.
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