Three-dimensional equivalent static analysis and design methodology of a reinforced concrete floating offshore wind turbine platform

Thesis (M.S., Civil Engineering)--California State University, Sacramento, 2014.This thesis presents a three-dimensional static analysis and design procedure for a floating offshore wind turbine support platform constructed of reinforced concrete. Results from a global performance analysis, which considers the dynamic interactions of wind and wave loading, from a conceptual case study by the American Bureau of Shipping are used to infer the equivalent static loading applied to the finite element model. Results from the analysis and applicable load combinations obtained from relevant design guidelines are used to design a floating concrete platform structure that includes precast and cast-in-place components as well as post-tensioning. The proposed concrete platform is a tri-floater, semi-submersible structure that consists of a cylindrical central core column to support the wind turbine tower, stabilized by the three buoyancy columns and a rigid pontoon base. The floating reinforced concrete support platform is shown to be an economically viable option when compared to steel platforms. Floating offshore wind turbine technology is a relatively new multi-disciplinary field of engineering where current design concepts primarily utilize steel floating support platforms. Reinforced concrete is advantageous over steel because of the durability of concrete exposed to a marine environment. Construction recommendations are discussed, as are social and economic considerations for floating offshore wind turbines.Civil Engineerin