The increase in investment in offshore wind farms and floating wind turbines due to environmental and energy needs has resulted in increased size of the rotors and going farther out to the sea where the winds are stronger. Consequently, the mooring systems must be designed for larger loads and deeper waters. With the trend towards deeper water applications, depending on the distance between the wind turbines in an offshore wind farm, the mooring load angle at the anchor’s padeye can vary from 30° in catenary systems up to more than 45° from the horizontal plane in taut systems. This fact highlights the importance of designing anchor systems with large vertical load components. A mechanical-empirical model for predicting the anchoring capacity of vertical and inclined piles in clay is developed. The model is based on a parametric study of 54 finite element models of inclined and vertical piles driven in extremely soft to very soft clay and subjected to anchoring loads at different angles. The model can estimate the capacity calculated by FEM with very good accuracy. In addition, the results show that pile inclination up to 30° can increase the mooring capacity by more than 50%. The study indicates that the reduced mooring capacity due to the large mooring angle of taut systems can partially be compensated by pile inclination.

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