Corrosion behavior of concrete fabricated with lithium slag as corrosion inhibitor under simulated acid rain corrosion action

Abstract

Concrete has great potential for local applications as a building material. Utilization of lithium slag in concrete can effectively and quickly solve its stacking problem. In this study, we used lithium slag to fabricate concrete and used a self-designed indoor dry-wet cycle spraying equipment to explore its acid rain corrosion resistance properties to promote its resource utilization because acid rain corrosion is very serious in Jiangxi Province. First, we investigated the fresh properties and the hardened properties of the concrete with lithium slag, and the mechanisms of acid rain corrosion resistance of concrete with lithium slag were studied. The study showed that lithium slag can accelerate the hydration reaction and improve the acid rain resistance of concrete, with better appearance integrity, and the lower decrease rate of compressive strength and mass loss of concrete. Unfortunately, lithium slag enhanced the neutralization depth of concrete. The compressive strength and mass loss of concrete with lithium slag are sensitive to the concentration of SO42−, and the neutralization depth is sensitive to the concentration of H+. Adding lithium slag can decrease the tendency for formation of CH crystals in the matrix, increase the hydration degree of cement, improve the microstructural compactness of concrete and decrease the Ca/Si of C–S–H gel. Therefore, lithium slag is beneficial for resisting the acid rain corrosion of concrete, and can be used as an acid rain corrosion inhibitor.