The case study describes how adopting an integrated and collaborative workflow between structural and geotechnical focused designers achieved significant and welcomed reductions in project risk and levelised cost of energy for the Seastar and Mermaid offshore wind farm substation platforms.
Each party implemented industry-leading design analyses able to be used for monopile foundations. SLPE performed the detailed structural design using a combination of time domain and spectral dynamic analysis techniques and employed Fugro’s soil‑structure interaction analysis expertise to implement the recommendations from the Pile Soil Analysis (PISA) joint industry project for foundation design.
SLPE’s team developed a dynamic analysis tool capable of capturing ringing effects, due to higher order wave loading, and modelling diffraction effects, including directionality, for appurtenances as well as p-δ effects and linear buckling. This comprehensive tool was used to compare DNV GL-type geotechnical modelling versus advanced soil modelling reaction curves derived between SLPE and Fugro. Fugro performed 3D finite element analysis using proprietary constitutive soil models to develop site-specific soil reaction curves for detailed structural analysis according to PISA. Using such bespoke models is shown to reduce costs and schedules when compared with more standard codified approaches, significantly reducing the foundation-related risks associated with the project.
Joe Hilton, Engineering Manager, SLPE, and Scott Whyte, Geotechnical Consultant, Fugro, will give the presentation.