Location

Shenzhen, P.R. China

Keywords

LC3; Cl- binding; corrosion; early age hydration

Abstract

Limestone Calcined Clay Cement (LC3) presents brilliant properties in binding Cl- so that the embedded steel bars are probably protected in Cl--contaminated condition, which meets the need of sea sand application. However, the corrosion performance of steel bars embedded in LC3 paste with Clis unclear, especially in early age hydration. Thus, a series of experiments were carried out to evaluate the corrosion performance of steel bars on initial and hardened stages of hydration, including concentration of OH- and Cl- in real pore solution, open circuit potential (OCP) and chemical elements of steel bars. In terms of early age hydration, the OCP of steel bars and ions concentration in pore solution indicated that both specimens embedded in PC and LC3 pastes were at a highly corrosion state, however, elemental results showed that no obvious corrosion happened at this stage. With respect to hardened age hydration, visual corrosion could be seen on PC-embedded steel bars, with more Fe3+ and O2-, in comparison with LC3-embedded one, which was related to the much lower absolute OCP and Cl- concentration in pore solution. Overall, LC3 cement demonstrates protective effect on steel bar in special contaminated-Cl- concentration.

【济南ICDCS】Submitted manuscript (with annotation at corrected sites).docx (911 kB)
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Corrosion Performance of Embedded Steel Bar in Cl--contaminated Limestone Calcined Clay Cement (LC3) at initial stage of hydration

Shenzhen, P.R. China

Limestone Calcined Clay Cement (LC3) presents brilliant properties in binding Cl- so that the embedded steel bars are probably protected in Cl--contaminated condition, which meets the need of sea sand application. However, the corrosion performance of steel bars embedded in LC3 paste with Clis unclear, especially in early age hydration. Thus, a series of experiments were carried out to evaluate the corrosion performance of steel bars on initial and hardened stages of hydration, including concentration of OH- and Cl- in real pore solution, open circuit potential (OCP) and chemical elements of steel bars. In terms of early age hydration, the OCP of steel bars and ions concentration in pore solution indicated that both specimens embedded in PC and LC3 pastes were at a highly corrosion state, however, elemental results showed that no obvious corrosion happened at this stage. With respect to hardened age hydration, visual corrosion could be seen on PC-embedded steel bars, with more Fe3+ and O2-, in comparison with LC3-embedded one, which was related to the much lower absolute OCP and Cl- concentration in pore solution. Overall, LC3 cement demonstrates protective effect on steel bar in special contaminated-Cl- concentration.