Effect of Concrete Performance on Corrosion Behavior of Pre-Rusted Rebar in Reinforced Concrete: Fid-Bau Portal

Effect of Concrete Performance on Corrosion Behavior of Pre-Rusted Rebar in Reinforced Concrete

Khoshroo, Moein / Ghoddousi, Parviz

This research focuses on a significant problem: the impact of self-compacting concrete’s quality on the decline in corrosion caused by the usage of pre-rusted rebar in reinforced concrete structures within the coastal environment of the Persian Gulf. To investigate this matter, the performance of self-compacting concrete and ordinary concrete was evaluated when utilizing pre-rusted rebar with varying degrees of rust. To enhance the quality of the concrete samples and ensure a more precise evaluation, silica fume, zeolite, and two different water-to-cement ratios were added to the concrete mixes. Several tests were conducted to assess the concrete’s quality, including viscosity, yield stress, water volume absorption, total porosity, compressive strength, electrical resistance, electrical conductivity, rapid chloride permeability, rapid chloride migration, and chloride diffusion coefficient. In addition, half-cell potential and intensity corrosion tests were performed to evaluate the steel corrosion in reinforced concrete. The findings indicate that the concrete’s quality and the corrosion of the rebar surface significantly influence the corrosion of pre-rusted steel in reinforced concrete. When rebars with different surface conditions, self-compacting concrete reduced corrosion intensity by 17% to 55% compared to ordinary concrete. Furthermore, adding supplementary cement materials and reducing the ratio of the water to cementitious material in self-compacting concrete resulted in a 13% to 48% greater reduction in the risk of corrosion compared to similar samples in ordinary concrete.