Random Field Analysis of Laterally Loaded Monopile Foundations
Publication: Geo-Risk 2023
ABSTRACT
Monopile foundation design for supporting offshore wind turbines has largely relied on classical p-y approaches originally developed for longer and more slender pile foundations. The shorter length and greater diameter of monopoles, however, has required empirical modification to the p-y approach to account for shear deformations and coupling between deflections and rotational deformations. Analysis of laterally loaded monopiles is fundamentally 3D, and recent studies have aimed to calibrate p-y springs using full 3D finite element analyses. This paper presents a preliminary study that uses a pseudo-3D approach suitable for modeling axisymmetric solids subjected to non-axisymmetric loading that is ideally suited for this type of geotechnical system. The method uses 2D finite element analysis in radial planes with circumferential variations modeled using a Fourier series. Soil property variation with depth is modeled using random fields. For risk assessment studies requiring Monte-Carlo simulations, the pseudo-3D approach offers greatly reduced computational costs compared with full 3D analysis. While the pseudo-3D approach is not new, it has not, to the authors’ knowledge, been combined with a random field description of soil properties. The results presented in this preliminary study focus on estimation of the probability of excessive lateral deformations at the submerged ground surface.
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Information
Published In
Geo-Risk 2023
Pages: 331 - 340
History
Published online: Jul 20, 2023
ASCE Technical Topics:
- Analysis (by type)
- Coasts, oceans, ports, and waterways engineering
- Continuum mechanics
- Disaster risk management
- Dynamic loads
- Dynamics (solid mechanics)
- Engineering fundamentals
- Engineering mechanics
- Finite element method
- Foundation design
- Foundations
- Geomechanics
- Geotechnical engineering
- Lateral loads
- Methodology (by type)
- Numerical methods
- Ocean engineering
- Offshore structures
- Pile foundations
- Risk management
- Soil mechanics
- Soil properties
- Solid mechanics
- Structural dynamics
- Three-dimensional analysis
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