Investigation of soil reaction curves extracted from 3D FE models-PPT Presentation

PPT Presentation

Pdf Summary

The presentation investigates soil reaction curves derived from three-dimensional finite-element (3D FEM) models for offshore wind turbine foundations. Belgium plans substantial offshore wind capacity expansion, and large-diameter monopiles remain the preferred foundation type in shallow waters.<br /><br />Foundation design must transfer loads while meeting ultimate, serviceability, and fatigue limit-state requirements; fatigue performance is especially important over a turbine’s 20-year design life. Common modeling approaches include beam-column models with nonlinear soil springs, macro-elements, and continuum models. The PISA method is considered particularly suited to offshore wind turbines, while detailed 3D FEM can represent soil behavior more fully but is computationally demanding.<br /><br />The research uses calibrated hypoplastic models for sand and clay, intended to capture soil response across small and large strains. The 3D FEM model was validated against centrifuge test results from Wang et al. (2021), then compared with 1D models through pushover analyses.<br /><br />The findings indicate that advanced, carefully calibrated 3D FEM models provide accurate soil stiffness estimates and are closer to monitoring data. However, the PISA method, using inputs from standard CPT tests, performs adequately and produces results comparable to 3D FEM. In particular, it can capture small-strain stiffness similar to that represented in the 3D models.

Keywords

offshore wind turbine foundations

3D finite element model

soil reaction curves

monopile foundation

fatigue limit state

PISA method

hypoplastic soil model

centrifuge test validation

soil stiffness

pushover analysis