Effect of the addition of red mud on the corrosion parameters of reinforced concrete

authors	Ribeiro, DV; Labrincha, JA; Morelli, MR
nationality	International
journal	CEMENT AND CONCRETE RESEARCH
author keywords	Concrete; Red mud; Diffusion; Corrosion; Electrochemical properties
keywords	CHLORIDE DIFFUSION-COEFFICIENTS; DURABILITY CHARACTERISTICS; ELECTRICAL-CONDUCTIVITY; EAF SLAG; PERMEABILITY; AGGREGATE; CEMENTS; BAUXITE; WASTE
abstract	Red mud, the main waste generated in aluminum and alumina production by the Bayer process, is considered "hazardous" due to its high pH. The characteristic of high alkalinity associated with the presence of alumino-silicates facilitates the assimilation and formation of compounds by reaction with chloride ions. The high pH also provides greater protection of rebars, which is reflected in the low corrosion potential and high electrical resistivity (filler effect) of concrete. In this study, the chloride concentration was monitored by measuring the conductivity of the anolyte. Red mud proved to be a promising additive for concrete to inhibit the corrosion process. The corrosion potential was monitored by electrochemical measurements and the electrical resistivity was evaluated using sensors embedded in concrete test specimens. The results showed that the addition of red mud is beneficial to concrete, reducing its chloride migration rate (diffusion coefficients) and corrosion potential and increasing its electrical resistivity. (C) 2011 Elsevier Ltd. All rights reserved.
publisher	PERGAMON-ELSEVIER SCIENCE LTD
issn	0008-8846
year published	2012
volume	42
issue	1
beginning page	124
ending page	133
digital object identifier (doi)	10.1016/j.cemconres.2011.09.002
web of science category	Construction & Building Technology; Materials Science, Multidisciplinary
subject category	Construction & Building Technology; Materials Science
unique article identifier	WOS:000298071500015