Experimental Study on Whole Wind Power Structure with Innovative Open-Ended Pile Foundation under Long-Term...

Area of Science:

• Geotechnical Engineering
• Structural Engineering
• Renewable Energy Systems

Background:

• Offshore wind energy (OWE) pile foundations endure significant horizontal cyclic loads from wind and waves.
• These cyclic loads alter the pile-soil system's stress, displacement, and dynamic characteristics.
• Cumulative deformation and potential structural damage necessitate understanding OWE pile foundation dynamics.

Discussion:

• Horizontal cyclic loading model tests were conducted on a 1:50 scale of the Burbo Bank 3.6 MW offshore turbine-foundation.
• The study investigated the influence of loading frequency and cyclic load ratio on the pile foundation's dynamic behavior.
• Results were compared with existing fitting formulas for maximum pile bending moment.

Key Insights:

• The bending moment of the OWE pile shaft correlates with loading frequency (f = 9 Hz) and loading cycles, as determined by fitting formulas.
• Under the tested conditions, fatigue damage to the OWE pile was not observed at low frequencies despite high loading cycles.
• This suggests a degree of resilience in OWE pile foundations under specific cyclic loading scenarios.

Outlook:

• Further research should explore a wider range of frequencies, load ratios, and soil conditions.
• Investigating the long-term cumulative effects and potential failure mechanisms is crucial for OWE infrastructure.
• Developing advanced predictive models for OWE pile foundation performance under complex cyclic loading is recommended.