Non-Destructive Evaluation of Concrete with Ultrasonic C-Scan and Digital Image Enhancement Techniques
This paper presents the results of Non-Destructive Evaluation (NDE) of concrete slabs using Ultrasonic C-Scan and image-enhancement algorithms for the detection and extraction of damage information from raw data. Two fabricated concrete slabs, one undamaged and the other with three rectangular voids were used for the test. Damage was evaluated by using ultrasonic through transmission C-Scan method. A 500 kHz transducer with pulse rates of 100 Hz to 5000 Hz was investigated to determine the best pulse rate for scanning concrete. The amplitude scan shows accurately the position of the voids present in the damaged concrete with respect to the reference edge. The results also show the inherent in-homogeneity of the concrete slab due to the presence of air pockets that invariably arise during the fabrication. Three statistical filtering techniques (Median, Mean and Gaussian) and one wavelet filtering technique were comparatively evaluated to enhance the quality of the digital image. The results show clearly the presence of the rectangular voids. Median filtering technique was the best in enhancing the image obtained from the C-Scan in terms of removing noise and preserving the details of the defects. Wavelet filtering technique was good in terms of overall noise reduction, but it resulted in loss of details of the defects producing a comparatively blurred image. This technique can be used to determine the quality of concrete at any stage in its working lifecycle thus making it a useful tool in the field of health monitoring of concrete.
A. C. Okafor and A. Dutta, "Non-Destructive Evaluation of Concrete with Ultrasonic C-Scan and Digital Image Enhancement Techniques," AIP Proceedings, American Institute of Physics (AIP), Jan 2013.
The definitive version is available at http://dx.doi.org/10.1063/1.4864920
40th Annual review of Progress in Quantitative Nondestructive Evaluation: Incorporating the 10th International Conference on Barkhausen Noise and Micromagnetic Testing
Mechanical and Aerospace Engineering
Keywords and Phrases
Nondestructive Testing; Ultrasonography; Image Enhancement; Medical Image Noise; Wavelets
Article - Conference proceedings
© 2013 American Institute of Physics (AIP), All rights reserved.