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Structural Monitoring and Maintenance Volume 9, Number 4, December 2022 , pages 373-388 DOI: https://doi.org/10.12989/smm.2022.9.4.373 |
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Depth estimation for surface-breaking cracks in steel-fiber reinforced concrete using ultrasonic surface waves |
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Ahmet S. Kirlangic and Zafer Iscan
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| Abstract | ||
| A USW based diagnostic procedure is presented for estimating the depth of surface-breaking cracks. The diagnosis is demonstrated on seven lab-scale SFRC beam specimens, which are subjected to the CMOD controlled three-point bending test to create real bending cracks. Then, the recorded multiple ultrasonic signals are examined with the signal processing techniques, including wavelet transform and two-dimensional Fourier transform, to investigate the relationships between the crack depth and two diagnostic indices, namely the attenuation coefficient and dispersion index (DI). Finally, the reliabilities of these indices for depth estimation are verified with the visually measured crack depths as well as the crack features obtained with a digital image processing algorithm. It is found that the DI outperforms the attenuation coefficient in depth estimation, where this index displays good agreement with the visual inspection for 86% of the inspected specimens. | ||
| Key Words | ||
| attenuation; condition assessment; crack depth estimation; dispersion; fiber-steel reinforced concrete; NDT for concrete; surface-breaking cracks; ultrasonic surface waves | ||
| Address | ||
| Ahmet S. Kirlangic: Department of Engineering, Teesside University, Middlesbrough, United Kingdom Zafer Iscan: Department of Electrical and Electronical Engineering, Faculty of Engineering and Natural Sciences, Bahcesehir University, Istanbul, Turkey | ||
