Corrosion Experimental Research on Local Damage of Epoxy-Coated Steel Bars in Concrete Under Marine Environment

Abstract

Epoxy coating has been proven to protect steel bars from corrosion. However, the damage of epoxy coating is inevitable, and this may lead to more serious corrosion of steel bar. In order to study the corrosion resistance of steel bars with damaged epoxy coating, two groups of coating-damaged bar and one group of coating-intact rebar were designed, and six specimens were made. The influence of electrolyte concentration on the corrosion rate of steel bars was studied by setting different concentrations. After 30 days of accelerated corrosion, electrochemical data were recorded by the electrochemical workstation. The experimental result shows that the steel bars with coating damage have obvious polarization curve characteristics of corrosion, and corrosion resistance decreases obviously. According to the corrosion current and potential, the larger the damaged area of the coating, the faster will be the corrosion rate. According to the polarization curve data, the polarization resistance is modified, and the result is closer to the real polarization resistance value. The calculated corrosion rate shows that the corrosion rate of reinforcement is affected by both electrolyte concentration and coating damage area, and electrolyte concentration has a greater influence on the corrosion rate.

Enhanced Weathering and Corrosion Resistance of Eu-Doped ZnO Solid Solution Material by Fluorescence Modification

“…Compared to the EP coating, the E corr of the ZEOSS composite shielding layer moved toward the cathodic region. According to previous research, this reflects the cathodic protection of the ZEOSS material . The parameter that changed most significantly is I corr , which is the accepted quantitative standard for corrosion reaction rate.…”

“…According to previous research, this reflects the cathodic protection of the ZEOSS material. 46 The parameter that changed most significantly is I corr , which is the accepted quantitative standard for corrosion reaction rate. Under the same conditions as the corroded substrate, a low corrosion current density indicates a high corrosion resistance of the coating.…”

Research on the Corrosion Behavior and Cathodic Protection of Defected-Epoxy-coated Reinforcement Exposed to Chloride Environment

“…Due to the diverse structure and complex service environment, the durability of the reinforced concrete caused by chlorine are prominent (Li et al 2019, Qu et al 2021. Epoxy coated-rebar is benefited with the high chemical stability and strong adhesion, helps to form an anti-corrosion barrier against external corrosive media on the surface of the steel bar, resulted in improving the corrosion resistance of the steel bar when applied in marine infrastructure (Cao et al 2022). However, the effectiveness of epoxy-coated rebar as a corrosion control method in reinforced concrete exposed to marine environment is still a controversial condition (Mao et al 2018, Sagues et al 1994.…”

Oxygen scavenging activity of smart colophony microcapsules containing nitrite corrosion inhibitors for steel reinforced concrete

“…The alkaline concrete environment favors the development of a stable passive film, which impart protection to the reinforcement surface (Macdonald et al, 2020). Concrete reinforcements, however, are susceptible to environmental degradation that can lead to corrosion of the structure (Bastidas et al, 2008;Cao et al, 2022). The major forms of corrosion for rebars used in reinforced concrete are caused by chloride ingress and carbonation, both of which initiate the formation of unstable ferrous oxides (Bastidas et al, 2020;Al-Ameeri et al, 2021).…”