Document Type
Article
Publication Date
12-13-2022
Publication Title
Remote Sensing
Volume
14
Abstract
Impact echo (IE) is a non-destructive evaluation method commonly used to detect subsurface delamination in reinforced concrete bridge decks. Existing analysis methods are based on frequency domain which can lead to inaccurate assessments of reinforced concrete bridge decks since they do not consider features of the IE signals in the time domain. The authors propose a new method for IE classification by combining features in the time and the frequency domains. The features used in this study included normalized peak values, energy, power, time of peaks, and signal lengths that were extracted from IE signals after they are preprocessed. We used a dataset containing IE data collected from four in-service bridges, annotated using chain dragging. A support vector machine (SVM) classifier was constructed using combined features to classify IE signals. A 1DCNN with unfiltered IE signals and a two-dimensional CNN using wavelet scalograms (2D representations of unfiltered IE signals) were also used to classify IE signals. The SVM model performed significantly better than the other models, with an accuracy rate, true positive rate, and true negative rate of 97%, 92%, and 98%, respectively. The SVM model also generated more accurate defect maps for all investigated bridges. IE data from the Federal Highway Administration’s InfoBridge website were used to investigate the efficacy of the developed models. The investigation yielded promising results for the proposed SVM model when used for a new set of IE data.
Issue
24
First Page
6307
DOI
10.3390/rs14246307
ISSN
2072-4292
Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Faezeh Jafari and Sattar Dorafshan. "Comparison between Supervised and Unsupervised Learning for Autonomous Delamination Detection Using Impact Echo" (2022). Civil Engineering Faculty Publications. 10.
https://commons.und.edu/cie-fac/10