Flanged foundation connection of the Offshore Wind Farm Amrumbank West - Concept, approval, design, tests and installation

Monopile (MP) foundations are the preferred foundation concept for offshore wind turbine generators (WTG) with soil conditions suitable for driving. Transition Pieces (TP's) are required for the connection of the driven MP to the tower of the wind turbine. The most commonly used connection between the MP and the TP is grouting of the annulus between MP and TP with fine grained high durability concrete, so called grouted joint. In the Amrumbank wind farm project a flanged connection is used. In this paper the concept of the flanged joint, main aspects of approval, design, procedure tests, manufacturing, prototype assembly and installation are described.