Correlation between surface concentration of chloride ions and chloride deposition rate in concrete. (21st February 2022)

• Record Type: Journal Article
• Authors: Lehner, Petr; Kubzová, Monika; Křivý, Vít; Konečný, Petr; Bujdoš, David; Rovnaníková, Pavla
• Is Part Of: Construction & building materials. Volume 320(2022)
• Publication Date: 2022-02-21
• Subjects: Concrete -- In-situ measurements -- Dry plate method -- Surface concentration -- Chloride; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.126183
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Correlation of concrete diffusion test and chloride in the air was done. The modified chloride penetration test and dry plate method were considered. Two locations under the bridges with highly different conditions were selected. Long term of exposure up two years was analysed and corelated. Good agree of curve of chloride in concrete and dry plate was observed. Abstract: This paper analyses the correlation function between the results of the time-consuming evaluation of chloride in concrete using the modified chloride penetration test and the significantly faster evaluation of the amount of chloride in the air using the dry plate method. Two in-situ locations in the Czech Republic were selected for long-term placement of samples, each with a highly different microclimate related to traffic intensity and different types of a bridge structure. Concrete samples were placed in-situ for 0.5, 1, 1.5, and 2 years of exposure. The dry plate method for obtaining the deposition rate of chloride was analysed each month and recalculated to the chlorides captured on the surface of the plate. There was good agreement in the amount of chloride increase in concrete and deposition plate during the winter, the increase of chlorides from de-icing agents, as well as a decrease in the summer period. In the measurements of concrete, the effect of chloride leaching from the upper layers was observed, even though the samples were partially hidden. The correlation found thus far needs to be verified in other locations in situ thus clarifying whether the dry plate method can fully replace the destructive examination of concrete structures.