Posters

Abstract

This research proposes an optimized design approach for piled onshore wind turbine foundations by relaxing the traditional no-gapping criterion, which typically requires that no tensile loads occur on piles under normal operational conditions. The current industry practice often leads to oversized and cost-intensive concrete foundation blocks to avoid gapping, increasing material use and construction costs without adequately addressing cyclic degradation risks. Our study shifts the focus from avoiding tensile loads to evaluating and limiting geotechnical capacity degradation under cyclic loading, using advanced cyclic loading analyses and interaction diagrams from EA-Pfähle standards. Setting a limit on pile degradation allows for a more precise evaluation of risks from cyclic loading, leading to safer and more informed design decisions compared to conventional implicit limits. Preliminary findings based on an real-world project demonstrate that this method can lead to significant reductions in foundation size—up to 25% in concrete volume—resulting in cost savings of €100k and a reduction of 100 tons of CO2 emissions per foundation. The results also indicate that, by carefully evaluation of degradation effects and adhering to a proposed limit of 25% on capacity degradation, the design maintains compliance with performance standards without compromising structural integrity. By challenging assumptions at the interface between wind turbine and civil design, this work proves that optimizations are achievable. This optimized strategy supports larger and more efficient wind turbine foundations while enhancing the sustainability and economic viability of wind energy projects, paving the way for the next standard for design of foundations on piles.