Simplified Equivalent Model for Seismic Centrifuge Testing of Offshore Wind Turbine Jacket Foundations

As offshore wind farms expand into seismically active regions, understanding the behavior of offshore wind turbine (OWT) foundations under seismic loading conditions by physical modeling is crucial. This study addresses the complexities of centrifuge modeling for prototype-scale OWT by developing a practical, simplified framework to represent a four-legged jacket structure for testing. A four-legged OWT jacket structure is simplified into an idealized cylindrical model with adjusted dimensions and mass distribution to maintain a similar natural frequency to the original. The models accuracy was validated through analytical calculations and finite element analysis using SAP2000. Results show that the natural frequency of the simplified model closely matches, with a difference of around 0.03 Hz, that of the original structure in both analytical and numerical assessments. This approach ensures dynamic consistency while meeting centrifuge constraints, providing a reliable basis for future physical testing and offering insights for seismic-resistant OWT design.