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Updated: Feb 6, 2026
Experimental Protocol to Determine the Chloride Threshold Value for Corrosion in Samples Taken from Reinforced Concrete Structures
Published on: August 31, 2017
Time-varying law of rebar corrosion rate in fly ash concrete
1State Key Laboratory for Geomechanics & Deep Underground Engineering, China University of Mining & Technology, Xuzhou, Jiangsu, 221116, China; Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Engineering, School of Mechanics and Civil Engineering, China University of Mining & Technology, Xuzhou, 221116, China; Department of Architecture, Faculty of Engineering, The University of Tokyo, Tokyo, 113-8654, Japan.
Abstract:
Whereas steel bar corrosion is the main cause for durability deterioration of existing reinforced concrete structures, it is important to understand the steel bar corrosion in concrete and predict the corrosion process in a sufficient way. In this paper, the corrosion process of rebar in ordinary concrete and three types of fly ash concrete specimens casted with 15%, 30% and 45% fly ash replacement ratios by mass under constant climate conditions were investigated. Meanwhile, the advanced digital video microscope measure system was used to study the microstructure of the steel/concrete interface at the different stages of corrosion. The effects of fly ash replacement were analyzed in terms of the electrical resistivity of concrete and the corrosion rate in the corrosion process of steel bars in fly ash concrete. The results showed that the resistivity of concrete increased with an increase in fly ash replacement, and the corrosion rate declined with the fly ash replacement increases. In addition, in fly ash concrete, the corrosion rate of plain bars were obviously smaller than that of ribbed bars.
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