Evaluation of self-healing in concrete by means of analytical techniques

0511548 - ÚTAM 2020 RIV CZ eng C - Conference Paper (international conference)
Aspiotis, K. - Sotiriadis, Konstantinos - Kumpová, Ivana - Mácová, Petra - Badogiannis, E. - Tsivilis, S.
Evaluation of self-healing in concrete by means of analytical techniques.
26. konference Betonářské dny 2019. Sborník přednášek. Praha: Česká betonářská společnost ČSSI, 2019 - (Jandová, K.; Nenadálová, Š.; Vích, J.). ISBN 978-80-907611-2-4.
[Betonářské dny /26./. Hradec Králové (CZ), 20.11.2019-21.11.2119]
Institutional support: RVO:68378297
Keywords : self-healing * concrete * chemical additives * Raman spectroscopy * X-ray tomography
OECD category: Construction engineering, Municipal and structural engineering

In the present work, the self-healing process in concrete was evaluated using analytical techniques. For this purpose, two concrete mixes of different composition (one used as reference) were prepared with a W/B of 0.45. The self-healing process was triggered by the introduction in the concrete mix of a commercial expansive admixture (calcium sulfo-aluminate), two dicarboxylic acids, and sodium carbonate salt. After 28 days curing in water, the specimens were artificially cracked (crack width ≈ 400 μm) and then again water-cured for 40 days until self-healing occurred. The progress of self-healing was investigated with a stereo-microscope at 40, 50 and 60 days. The efficiency of the process was evaluated using micro-Raman spectroscopy and X-ray micro-computed tomography (XmCT). Significant reduction in the crack width was observed as a result of filling the crack with calcite generated during the self-healing process. In some cases, the crack was completely healed. The experimental methodology used provided new insights into the evolution of the self-healing phenomenon in concrete.
Permanent Link: http://hdl.handle.net/11104/0302900