LARGE DEFORMATION FINITE ELEMENT ANALYSIS ON THE INSTALLATION OF INTEGRATED DRAG ANCHOR-CHAIN SYSTEM IN SANDY SEABED

The offshore wind industry is expanding from shallow waters to deep waters and from bottom-fixed to floating wind turbines. As a cost effective and efficient type of anchoring foundations, drag anchors have been widely used for mooring floating offshore structures. However, there is currently no well-established calculation method for predicting the installation trajectory of drag anchors in sand. This paper proposes a large deformation finite element analysis approach based on coupled Eulerian Lagrangian (CEL) method. By simplifying the chain geometry and use of appropriate connectors between chain links, an integrated drag anchor-chain model is established. The results of the large deformation finite element analyses are compared with those of physical model experiments. The comparison demonstrates good accuracy and reliability of the numerical model. The large deformation analysis approach proposed in this paper provides a powerful tool for further investigation on drag anchor installation behaviour in sand.