Floating offshore wind (FOW) is a rapidly expanding sector critical to achieving net-zero targets, particularly in deep-water regions such as the northern North Sea. The performance of anchoring and mooring systems is fundamental to the stability and safety of these structures. However, anchor design and installation in glaciated continental shelves remain highly uncertain due to complex seabed conditions.
Glaciogenic sediments—characterised by dense tills, gravel and cobble lag deposits, and shallow bedrock—exhibit strong spatial variability and contrasting geotechnical properties. These conditions frequently result in anchor installation challenges, including refusal, unpredictable embedment, and variable penetration behaviour. Furthermore, the influence of glacial geomorphological features (e.g. eskers, moraines, iceberg plough marks) adds an additional layer of complexity.
Looking to the future, many FOWs will require decommissioning in the coming decades. There is an urgent need to understand how anchors behave not only during installation but also during extraction. Anchors that are difficult to install may also be challenging to remove, introducing uncertainty in project cost, environmental impact, and operational risk. Despite this, the lifecycle behaviour of anchors in glacial seabeds remains poorly understood.
Aim
This project aims to develop a comprehensive understanding of the lifecycle performance of FOW anchors in glaciogenic seabed conditions, with a focus on both installation and decommissioning.
Objectives
- Characterise the geotechnical properties and geomorphological variability of glacial seabeds relevant to anchoring.
- Evaluate the performance and suitability of major FOW anchor types (e.g. drag anchors, suction caissons, driven piles, plate anchors) in such environments.
- Identify key risks associated with anchor installation, including refusal and erratic embedment behaviour.
- Investigate anchor removal mechanisms and challenges in glacial sediments.
- Quantify how commissioning decisions influence decommissioning feasibility, cost, and environmental impact.
- Critically assess current laboratory testing methods for anchor–soil interaction in heterogeneous sediments.
- Evaluate and recommend numerical modelling approaches for simulating anchor behaviour across the full lifecycle.
Methodology
The project will adopt an integrated experimental–numerical approach:
- Data synthesis and site characterisation: Compilation and analysis of geological and geotechnical datasets from glaciated offshore regions to define representative ground conditions.
- Laboratory testing: Physical modelling of anchor embedment and extraction in controlled conditions, incorporating layered and heterogeneous sediment analogues representative of glacial deposits.
- Numerical modelling: Application of advanced numerical techniques (e.g. finite element and discrete element methods) to simulate anchor–soil interaction under complex stratigraphic and geomorphological conditions.
- Scenario-based lifecycle analysis: Assessment of different anchor strategies, linking installation performance with decommissioning outcomes (e.g. required extraction forces, risks, and costs).
