Title: Evaluation of internal defects in reinforced concrete by means of innovative AE tomography

Authors: Takahiro Nishida; Tomoki Shiotani; Hisafumi Asaue

Addresses: Kyoto University, C3-b4S16, Katsura Campus, Nishikyo-ku, Kyoto 615-8540, Japan ' Kyoto University, C3-b4S16, Katsura Campus, Nishikyo-ku, Kyoto 615-8540, Japan ' Kyoto University, C3-b4S16, Katsura Campus, Nishikyo-ku, Kyoto 615-8540, Japan

Abstract: The purpose of this study is to detect the location of internal defects in reinforced concrete columns by innovative AE tomography. The results showed that elastic wave velocity in the major part of bodies of the tested columns was lower than 2500 m/sec. Also, according to concrete core samples taken from the tested columns, elastic wave velocities of the cracked or fractured zones were lower than velocities in other zones. In addition, 'concrete quality designation' (CQD) values were calculated for the concrete core sample and compared with the elastic wave velocity. As a result, the average velocity showed good correlation with CQD values for the core sample. On the basis of the results, defects in concrete can be evaluated by means of elastic velocity distribution obtained as a result of the proposed AE tomography.

Keywords: AE tomography; 3D elastic wave velocity distribution; internal defects; CQD; concrete quality designation.

DOI: 10.1504/IJMMP.2017.087682

International Journal of Microstructure and Materials Properties, 2017 Vol.12 No.1/2, pp.66 - 78

Received: 17 Feb 2017
Accepted: 16 Jun 2017
Published online: 30 Oct 2017 *

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