Mooring systems constitute an important element to secure the stability and survival of floating structures. In the last years, its use has increased potentially linked to the growth of marine renewable energies, about all, offshore wind and waves. Traditionally, fixed foundations such as gravity, monopiles or jackets have been installed. However, new alternatives have been developed based on floating structures looking to take advantage of the potential resource in deep waters.
This paper involves an exhaustive mooring system study based on catenary configuration from different points of view. Physical modelling was performed by means of different experimental tests under different loading conditions including prescribed movements and natural forcing (waves and currents) considering two different types of seabed: a rigid seabed using the glass of the flume simulating a rocky bottom and a deformable seabed through sandy seabed. Different types of numerical approaches were implemented and they were validated with laboratory tests. Quasi-static and dynamic models were included. Also, a commercial software called SESAM was used to verify the results. Finally, the effect of wave groupiness on extreme loads was analysed using a Floating Offshore Wind Turbine (FOWT).