Electrochemical Impedance Spectroscopy to Study the Carbonation Behavior of Concrete Treated with Corrosion Inhibitors

Abstract

In this paper, electrochemical impedance spectroscopy was used as non destructive technique (NDT) for studying the carbonation behavior of the concrete sample treated with migratory type of organic corrosion inhibitors. Concrete carbonation was achieved in carbonation chamber by maintaining 5% CO 2 by volume, 60-70% relative humidity and 30 ± 2°C temperature for 90 days. The experimental results show that with progressive carbonation, porosity of the concrete reduces and results in denser microstructure. The concrete surface treated with corrosion inhibitor C.I. 1 (amine -ether based) and C.I. 2 (2-aminobenzoic acid) shows the behaviour different form the control sample at the end of exposure conditions. Impedance results indicate that carbonation depth can be predicted by analyzing the high frequency arc of Nyquist plot. Also, both of the tested inhibitors were able to form a passive layer around the rebar surface and their efficiencies improved with time.

Corrosion inhibition mechanism of aromatic amino acids for steel in alkaline pore solution simulating carbonated concrete environment

“…[31,32] A few other researchers also chose similar testing ages to study the performance of different corrosion inhibitors in pore solutions. [33][34][35] All electrochemical tests were carried out in a standard threeelectrode cell (steel specimens as WE, platinum as counter electrode, and saturated calomel as reference electrode) in open-air room temperature conditions (25 ± 2°C) using Gill AC Corrosion Analyzer: Serial no. 1924 (electrochemical setup displayed in Figure 3).…”

Evaluation of Concrete Carbonation Based on a Fiber Bragg Grating Sensor

“…Nevertheless, these methods are currently confined to laboratory settings and are inherently destructive, rendering them unsuitable for large-scale structures and critical components in engineering projects. Recently, non-destructive testing methods have been applied to the study of concrete carbonation, such as non-linear ultrasonic techniques [ 21 ], resistivity measurement [ 22 , 23 ], and electrochemical impedance spectroscopy [ 24 ], etc. Kim used a non-contact air-coupled transducer to detect Rayleigh wave signals and obtained the nonlinear parameters of the material.…”

Evaluation of corrosion inhibition capability of graphene modified epoxy coatings on reinforcing bars in concrete

“…It is not possible to eliminate altogether corrosion occurring in concrete but several corrosion control strategies which focus on either altering the corrosion mechanism or delaying the same have been reported. Researchers have reported to delay corrosion of reinforcing steel by reducing permeability of the concrete by introducing admixtures in concrete mix like fly ash, polymer fibers or healing microcapsules [9][10][11][12][13][14], or by applying coats or surface treatments on the concrete surface to make it impermeable [15][16][17][18][19], or by using corrosion inhibitors which prevent the entry of aggressive ions into the concrete [20][21][22][23]. Use of protective/sacrificial coatings on the reinforcing steel like galvanization, epoxy-based coatings, and zinc based cathodic protection etc.…”