Chloride redistribution and reinforcement corrosion in the interfacial region between substrate and repair concrete - a laboratory study
2008 (English)In: Materials and Structures, ISSN 1359-5997, E-ISSN 1871-6873, Vol. 41, no 6, 1001-1014 p.Article in journal (Refereed) Published
One of the most common deterioration mechanisms in concrete structures is reinforcement corrosion caused by chlorides. An often used repair strategy is to remove the damaged concrete and sometimes also undamaged concrete and replace with a repair concrete. The chloride contaminated undamaged concrete and the repair concrete have to be compatible in order to achieve a durable system. This laboratory study has investigated 13-year-old reinforced concrete specimens with both substrate concrete with mixed-in chlorides and an initially chloride free repair concrete. The main objective was to study chloride transport from the contaminated substrate concrete into the repair concrete and establish chloride profiles across the interfacial region and interfacial zone between the two materials. Another objective was to evaluate the location of reinforcement corrosion in the interfacial zone, in the substrate concrete and in the repair concrete. The main results from this laboratory investigation show that reinforcement corrosion occurs in and near the interfacial zone between chloride contaminated and repair concrete. It was found that the corrosion occurs in local areas with passive steel areas between, i.e. macrocell corrosion. The chlorides are transported from the contaminated substrate concrete into the repair concrete. This investigation indicates that there is a risk for reinforcement corrosion around a patch repair when the substrate concrete has chloride contents exceeding 1.0 wt% by weight of cement.
Place, publisher, year, edition, pages
2008. Vol. 41, no 6, 1001-1014 p.
chloride transport, reinforcement corrosion, concrete repair, compatibility, steel
IdentifiersURN: urn:nbn:se:kth:diva-17578DOI: 10.1617/s11527-007-9301-6ISI: 000256434800001ScopusID: 2-s2.0-44649171629OAI: oai:DiVA.org:kth-17578DiVA: diva2:335622
QC 20100525. Tidigare Titel: "Chloride transport and corrosion near the transition zone between substrate and repair concrete - laboratory study".2010-08-052010-08-052010-11-29Bibliographically approved