I-SonReb: an improved NDT method to evaluate the in situ strength of carbonated concrete

Abstract

Concrete strength evaluated in situ by means of the conventional SonReb method can be highly overestimated in presence of carbonation. This latter, in fact, is responsible for the physical and chemical alteration of the outer layer of concrete. As most of the existing concrete structures are subjected to carbonation, it is of high importance to overcome this problem. In this paper, an Improved SonReb method (I-SonReb) for carbonated concretes is proposed. It relies on the definition of a correction coefficient of the measured Rebound index as a function of the carbonated concrete cover thickness, an additional parameter to be measured during in situ testing campaigns. The usefulness of the method has been validated showing the improvement in the accuracy of concrete strength estimation from two sets of NDT experimental data collected from investigations on real structures.

Keywords::

• concrete strength
• existing structures
• non-destructive techniques
• SonReb method
• carbonation

Acknowledgements

Authors would like to thank MOST S.r.l. for providing the experimental data used in this research project.

Disclosure statement

No potential conflict of interest was reported by the authors.