“TRIWIND” is the development of a floating concrete platform for the installation of offshore wind turbines.
Floating platforms are necessary for the installation of offshore turbines when depths exceed 50 m. Due to the corrosive and fatigue loading effect in the marine environment, a steel marine construction is generally optimally designed for a useful life of 20 to 30 years and must be regularly inspected and maintained. A steel platform for a 5 MW offshore wind turbine requires at least 1,000 tons of steel, it could even double. Steel designs could be transferred to concrete with a useful life of up to 100 years.
Triwind Float is a high-performance floating platform with an innovative and efficient construction, assembly and commissioning system that represents considerable cost savings, a much shorter lead time compared to existing platforms and maximum safety. The platform that weighs about 28.5 tons and requires a concrete volume of 11,400 m3
It is made up of a concrete structure whose construction is based on the technology, widely used in Spain, of port caissons for the construction of docks and piers. It consists of a base formed by a prismatic concrete structure and exterior vertical walls and an internal frame of vertical walls that form cells that are closed at the bottom and at the top. Despite the great efforts to which it will be subjected, and the great moment transmitted by the wind turbine that has to compensate, the concrete of the entire structure hardly suffers bending. The main stress on the structure is compression. This is achieved by its own geometry and configuration.
The proposed platform, together with the superstructure that it supports (wind turbine) has an initial draft (around 10 m), which significantly increases the availability of docks near the place of implantation for their construction. This allows a complete onshore installation to be carried out and towed to its location in a vertical position, presenting great naval stability, high natural period in which it swings and low resistance to displacement.
The platform has an optimal hydrodynamic behaviour, avoiding and minimizing possible resonances between the waves, the wind, the structure, the tower mooring system and the wind turbine.
BERENGUER INGENIEROS and UNIVERSIDAD POLITÉCNICA DE MADRID participate in the project.