Experimental Study on Interface Debonding Defect Detection and Localization in Underwater Grouting Jacket Connections...

Area of Science:

• Engineering
• Materials Science
• Non-destructive Testing

Background:

• Grouting jacket connections (GJCs) are crucial for offshore wind turbine support structures.
• Interface debonding between grouting materials and steel tubes in GJCs compromises mechanical integrity.
• Effective defect detection is vital for ensuring the safety and longevity of these structures.

Purpose of the Study:

• To experimentally validate a surface wave-based approach for detecting and localizing interface debonding in underwater GJC specimens.
• To investigate the influence of debonding defect dimensions on piezoelectric lead zirconate titanate (PZT) sensor signals.
• To develop a visualization method for debonding regions using PZT actuation and sensing.

Main Methods:

• Fabrication of scaled underwater GJC specimens with artificial interface debonding defects.
• Utilizing piezoelectric lead zirconate titanate (PZT) for surface wave actuation and sensing.
• Employing one pitch and one catch (OPOC) and one pitch and multiple catch (OPMC) configurations.
• Analyzing output voltage signals to identify abnormal wave propagation paths.

Main Results:

• Systematic study of the influence of debonding height and circumferential dimension on PZT sensor signals.
• Successful detection and localization of artificially mimicked interface debonding defects.
• Visualization of debonding defect regions through the intersection of identified abnormal wave paths.
• Experimental confirmation of the method's feasibility for underwater GJCs.

Conclusions:

• The proposed surface wave measurement technique effectively detects and localizes interface debonding in underwater GJCs.
• This non-destructive approach offers a promising solution for structural health monitoring of offshore wind turbine foundations.
• The method provides a novel way to visualize and assess the integrity of GJC components.