Effect of surface-treated energy optimized furnace steel slag as coarse aggregate in the performance of concrete under corrosive environment

Abstract

Extraction of a massive volume of stone aggregate from the earth harms the environment through deforestation, air pollution, wasteland development (exhausted quarries), etc. On the other hand, dumping of tons and tons of slag from steel industries occupies more land area and causing pollution. Energy Optimized Furnace (EOF) steel slag (from JSW steels, Macheri, Salem, Tamil Nadu, India) is proposed as a substitute for the natural aggregate utilized in structural concrete. The main objective of the study is to improve the corrosion resistance of steel slag concrete. The porous structure of steel slag affects the durability properties of the concrete made with steel slag. The surface of EOF steel slag was treated with fly ash: cement slurry coating. The effectiveness of the surface treatment on steel slag in concrete was compared with steel slag concrete using corrosion inhibitor. In this present study, concrete specimens were prepared with EOF steel slag, surface-treated steel slag, and steel slag and corrosion inhibitor. The slag concrete was studied for its compressive strength, chloride ion permeability, and risk assessment of steel reinforcement corrosion embedded in concrete. The strength of EOF steel slag concrete is significantly acceptable. The surface modification of steel slag with fly ash: cement proved its significance by reducing the permeability of steel slag concrete. Since, the pores in the steel slag were filled entirely with pozzolanic gel with reduced interconnectivity of the pores. The surface modification of steel slag enhanced the corrosion resistance of steel slag concrete by taking longer times to reach high corrosion potentials.