Coupled dynamic response analysis of a novel steel-concrete hybrid semi-submersible platform for floating offshore wind turbines

The utilization of concrete structural materials demonstrates significant potential for cost reduction in floating offshore wind turbine platforms owing to their inherent cost-effectiveness. This study proposes a novel steel-concrete hybrid (SCH) semi-submersible platform with a three-column configuration for floating offshore wind turbines. A detailed numerical model integrating aero, hydro, servo, elastic, and mooring dynamics was created to thoroughly examine the platform's dynamic responses in intermediate water depths (65 m). A comparative analysis was performed to evaluate the hydrodynamic performance between the steel-concrete hybrid platform and a geometrically equivalent all-steel semi-submersible platform. Results reveal that the proposed SCH platform exhibits enhanced hydrodynamic characteristics. Specifically, the SCH platform demonstrates superior performance in surge, mooring line tension, and nacelle acceleration when compared to its steel counterpart.