Distributed Fiber Optic Shape Sensing of Concrete Structures

Area of Science:

• Civil Engineering
• Materials Science
• Sensor Technology

Background:

• Civil structural health monitoring (CSHM) is increasingly vital due to global construction growth and aging infrastructure.
• Distributed fiber optic sensing (DFOS) effectively measures strain and temperature but often excludes curvature and bending analysis.
• Existing methods struggle to fully integrate shape sensing capabilities into CSHM for concrete structures.

Purpose of the Study:

• To comprehensively study and compare various distributed fiber optic sensing (DFOS) approaches for shape sensing in concrete structures.
• To evaluate the performance of different DFOS sensors and installation techniques under realistic structural testing conditions.
• To determine the feasibility and reliability of DFOS for assessing the bending behavior and overall shape of concrete elements.

Main Methods:

• Testing of different DFOS sensors and installation methods on concrete beams under load.
• Utilizing fully-distributed sensing units and fiber Bragg grating interrogators for data acquisition.
• Conducting real-scale load tests on tunnel lining segments with integrated DFOS systems.

Main Results:

• Significant variations in performance were observed among the different DFOS sensing systems and installation techniques.
• The study demonstrated that DFOS can provide highly reliable shape sensing data for concrete structures.
• Successful quantification of strain, temperature, and bending-related deformation was achieved.

Conclusions:

• DFOS is a viable technology for advanced CSHM, particularly for shape sensing in concrete structures.
• The selection of appropriate DFOS systems and installation strategies is critical for successful implementation.
• Future CSHM applications can benefit from tailored DFOS solutions for precise structural behavior assessment.