Uplift Behaviour of Screw Piles for Offshore Deepwater Wind Turbine Foundations

The two main types of foundations used so far for offshore wind energy applications are the conventional solution, the so-called mono-piles and the less conventional suction caissons. In the case of the monopiles cyclic loading is identified as the main issue to be considered, and for suction caissons, a quite large number of design issues are present, but prevalent on the others, is the tension capacity. The idea to extend screw piles to offshore applications is becoming nowadays actual. This type of foundation has a quite large onshore application but not offshore so far. They have excellent promise for the wind turbines in deep water because of the very good combination of compression and tension capacity. The attention in this work is focussed on the tension capacity, this is done through a parametric analysis where the parameters are the pile and flanges diameter, the number of piles, the spacing between piles and the pitch of the helix. The commercial finite element analysis software Abaqus CAE combined with the Python scripting is used for the solution of tension capacity of this problem.