Strength recovery of concrete exposed to freezing-thawing by self-healing of cementitious materials using synthetic fiber 

¹Department of Civil and Environmental Engineering, Kitami Institute of Technology, Hokkaido, 090-8507, Japan

²Faculty of Environmental Technology, Muroran Institute of Technology, Hokkaido, 090-8585, Japan

Adv. Mater. Lett., 2017, 8 (10), pp 993-998

DOI: 10.5185/amlett.2017.1635

Publication Date (Web): Jul 22, 2017

Copyright © IAAM-VBRI Press

E-mail: hs-choi@mail.kitami-it.ac.jp

Abstract

In this study, it is possible to disperse effectively cracked using synthetic fiber, an examination of the most suitable self-healing conditions was performed on the above crack width 0.1mm. As a result, effective crack dispersion using polyvinyl alcohol (PVA) fibers with polar OH^- groups, as well as improved self-healing for cracks that are larger than 0.1 mm in width, posing concerns of CO₂ gas and Cl^- penetration, were observed. Also, CO₃^2- reacts with Ca²⁺ in the concrete crack, resulting in the precipitation of a carbonate compound, CaCO₃. Based on this, it is deemed possible for the recovery of effective water tightness and strength recovery through effective freezing-thawing resistance to be made from cracks that are larger than 0.1 mm in width. In addition, it was determined that, as for the most suitable self-healing conditions in the inside and surface of the cracks, calcium hydroxide (Ca(OH)₂) solution with CO₂ micro-bubble was more effective in promoting the self-healing capability than water with CO₂ micro-bubble. 

Keywords

Freeze-thaw, micro-crack, PVA fiber, CO₂ micro-bubble, self-healing, water tightness, strength recovery.