Damage Localization of Beam Bridges Using Quasi-Static Strain Influence Lines Based on the BOTDA Technique.

Area of Science:

• Structural Health Monitoring
• Optical Sensing Technologies
• Civil Engineering

Background:

• Quasi-static strain influence lines (ILs) show promise for bridge damage diagnosis.
• Limitations include sparse measurement points and varying load conditions, hindering accurate damage localization.
• Existing methods struggle with inconsistencies between pre- and post-damage loading scenarios.

Purpose of the Study:

• To improve the accuracy and reliability of damage localization in bridge superstructures.
• To overcome the challenges posed by limited strain measurement points and load condition variations.
• To introduce a novel damage localization index for beam bridges.

Main Methods:

• Application of Brillouin optical time domain analysis (BOTDA) to significantly increase strain measurement points.
• Development of a damage localization index based on quasi-static strain ILs.
• Validation through numerical simulations and experimental quasi-static testing of a model bridge.

Main Results:

• Successful application of BOTDA for enhanced strain data acquisition in bridge monitoring.
• Demonstration of the proposed damage localization index's independence from load condition variations.
• Accurate localization of damage in a beam bridge superstructure validated by numerical and experimental data.

Conclusions:

• The integrated approach using BOTDA and the novel index effectively addresses limitations in traditional bridge damage localization.
• The proposed method offers a robust and accurate solution for identifying structural damage in bridges.
• This technique holds significant potential for improving bridge safety and maintenance strategies.