A method to measure small local strains in concrete surfaces using its natural texture and image cross‐correlation

Structural Control and Health MonitoringVolume 26, Issue 9 e2410 RESEARCH ARTICLE A method to measure small local strains in concrete surfaces using its natural texture and image cross-correlation Belen Ferrer, Belen Ferrer Department of Civil Engineering, Universidad de Alicante, Alicante, SpainSearch for more papers by this authorJulian Espinosa, Julian Espinosa Inst. of Physics Applied to the Sciences and Technologies, Universidad de Alicante, Alicante, SpainSearch for more papers by this authorDavid Mas, Corresponding Author David Mas david.mas@ua.es orcid.org/0000-0002-9206-4591 Inst. of Physics Applied to the Sciences and Technologies, Universidad de Alicante, Alicante, Spain Correspondence David Mas, Inst. of Physics Applied to the Sciences and Technologies, Universidad de Alicante, Alicante, Spain. Email: david.mas@ua.esSearch for more papers by this author Belen Ferrer, Belen Ferrer Department of Civil Engineering, Universidad de Alicante, Alicante, SpainSearch for more papers by this authorJulian Espinosa, Julian Espinosa Inst. of Physics Applied to the Sciences and Technologies, Universidad de Alicante, Alicante, SpainSearch for more papers by this authorDavid Mas, Corresponding Author David Mas david.mas@ua.es orcid.org/0000-0002-9206-4591 Inst. of Physics Applied to the Sciences and Technologies, Universidad de Alicante, Alicante, Spain Correspondence David Mas, Inst. of Physics Applied to the Sciences and Technologies, Universidad de Alicante, Alicante, Spain. Email: david.mas@ua.esSearch for more papers by this author First published: 21 June 2019 https://doi.org/10.1002/stc.2410Citations: 4Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Summary This paper proposes a method to measure the displacement of every point on a concrete surface using its original surface texture and digital image cross-correlation (DICC). The main advantage is that it does not need to add or attach any particular pattern or target to the surface, contrary to the current methods based in DICC. The method is tested in a concrete probe during loading–unloading cycles under its yield limit, with no cracks appearing in the surface. The total surface of the probe was tessellated in optimal local areas, and DICC with peak refinement was performed on each local area. In order to find the optimal size for that areas, we propose here a method based on the image local entropy. We show that, with natural nonoptimized textures, the proposed technique allows to locally measure the concrete deformation due to small strains (<0.1%) with an error below 50 με. Although results are more inaccurate than those obtained by a strain gauge, our method is able to noninvasively determine the strains in a concrete surface under small loads with reasonable accuracy, thus allowing its use in unreachable or historical structures where no attachment or target painting is possible. Citing Literature Volume26, Issue9September 2019e2410 RelatedInformation