Nonlinear analysis of offshore wind towers in prefabricated segments of prestressed fibre reinforced concrete

Abstract

This paper presents the nonlinear finite element analysis of a new concept of offshore wind tower made by prefabricated prestressed fibre reinforced concrete (FRC) segments that are assembled to form the final structure. Fibre reinforcement aims to eliminate conventional passive steel reinforcement in order to avoid corrosion concerns and decrease the thickness of the segments. The first stage of the design approach consists on an analytical model that optimizes the geometry of the eolic tower by considering the relevant loading cases, the properties of the developed FRC, the resisting stress levels of the constituent materials and the frequency and lateral deformability of the tower. By determining the thickness and radius along with the height of the tower, this model can provide the solution of minimum FRC volume for the eolic tower. In the second stage of the design approach, the optimum solution from the previous design stage is simulated by a finite element approach that considers the geometric and material nonlinear features. This paper describes the main relevant aspects of this design methodology.