Title:
Comparison of Nondestructive Methods for Detecting Reinforcing Bar Placement
Author(s):
David C. Burney, Kimberly E. Kurtis, Laurence J. Jacobs, and Ryan J. Sherman
Publication:
Materials Journal
Volume:
121
Issue:
6
Appears on pages(s):
27-40
Keywords:
cover; dowel; eddy current; epoxy-coated; galvanized; ground-penetrating radar (GPR); quality assurance; stainless steel
DOI:
10.14359/51742260
Date:
12/1/2024
Abstract:
Despite improvements in nondestructive testing (NDT) technologies, the quality assurance of concrete reinforcing bar placement is still primarily conducted with conventional methodologies, which can be time-consuming, ineffective, and damaging to the concrete components. This study investigated the performance of two commercially available cover meters and one groundpenetrating radar (GPR) device. A cover meter was found to have the greatest accuracy for depths smaller than 3.19 in. (81.0 mm), while the GPR performed better for greater depths. The effect of reinforcing bar depth, diameter, and type; neighboring reinforcing bars; and concrete conditioning on the performance of the devices was quantified. The use of epoxy-coated reinforcing bar, galvanized reinforcing bar, and stainless-steel reinforcing bar were found to have a negligible effect on cover meter accuracy. A model was developed to predict the precision of the GPR post-measurement analysis given a depth and concrete dielectric constant.
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