The effectiveness of alternative stiffening types of the cutout provided near the base of tubular steel wind turbine towers is assessed, taking into account the dynamic nature of wind loading. To that effect, artificial wind load time histories are first obtained using the public domain aero-elastic code FAST. Finite element models that have been previously validated by means of comparison with experimental results, are then used to carry out fully nonlinear dynamic analyses and compare strength and overall structural performance.

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