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Defect Detection and Characterization in Concrete Based on FEM and Ultrasonic Techniques
Jeongnam Kim1, Younho Cho2, Jungwon Lee3
1Graduate School of Mechanical, Pusan National University, Pusan 43241, Republic of Korea.
Materials (Basel, Switzerland)
|November 26, 2022
Summary
Finite element analysis and experiments accurately estimate concrete crack depth using time-of-flight measurements. This validated method enhances structural safety assessments and crack detection in real-world applications.
Area of Science:
- Materials Science
- Civil Engineering
- Non-Destructive Testing
Background:
- Accurate crack depth estimation is crucial for concrete structure integrity.
- Traditional methods may lack precision or be invasive.
- Time-of-flight (ToF) offers a potential non-destructive approach.
Purpose of the Study:
- To validate finite element analysis (FEA) for concrete crack depth estimation using ToF.
- To compare FEA results with experimental data.
- To present methodologies for crack detection and depth evaluation in concrete structures.
Main Methods:
- Performed FEA and experimental tests on concrete blocks with known crack depths (0 mm, 45 mm, 70 mm).
- Measured time-of-flight changes by varying transmitter and receiver positions.
- Applied various formulas to calculate defect depth from experimental measurements.
Main Results:
- FEA results showed strong agreement with experimental findings.
- High accuracy was confirmed for defect depth calculation formulas.
- Methodologies were presented and validated through field cases.
Conclusions:
- FEA combined with ToF is a highly accurate method for estimating concrete crack depth.
- The validated approach improves structural soundness and safety evaluations.
- This research provides practical methodologies for concrete structure assessment.
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