Suction Buckets

Suction Buckets are large cylindrical shells that are used as foundation structures for offshore wind turbines. During installation, they are sucked into the ground by negative pressure. Due to the low-noise installation and the possibility of complete dismantling, they are environmentally friendly and are considered a promising alternative to the common pile foundations of offshore wind turbines. However, the installation process requires a very detailed interdisciplinary analysis. A negative pressure must be applied that is large enough to insert the bucket, but still does not lead to hydraulic negative pressure or buckling. Shell buckling is a stability problem and for cylindrical shells the most critical failure mode. However, the calculation of the critical buckling load is very complex, it depends very much on geometrical imperfections but also on boundary conditions. The buckling analysis can be performed with different analysis concepts of varying complexity, from membrane theoretical calculation to material and geometrical nonlinear analysis with imperfections. Numerical models are required to consider the imperfections and boundary conditions in a realistic way.