Electric arc furnace slag concrete

The aim of this section is to comprehensively investigate the possibility of substituting natural aggregates with Black/Oxidizing Electric Arc Furnace (EAF) slag, at high replacement ratios, to produce structural concrete. The properties of the slag are described in detail, in terms of chemical composition, mineralogy, microstructure and physical characteristics. A review of the main physical and mechanical properties of concrete containing EAF slag is reported, analyzing the effect of the substitution on compressive and tensile strength and on elastic modulus, both for producing ordinary strength and high strength concretes. Durability-related properties in aggressive environments are also discussed, paying attention on freezing/thawing, drying/wetting conditions, and chlorides-contaminated exposure. Results showed that high substitution ratios of coarse natural aggregates are possible without decreasing mechanical properties of concrete, and on the contrary, slag use enhances concrete strength. Conversely, replacement of fine natural aggregates with fine slag seems feasible at lower substitution ratios only. Presence of calcium and magnesium oxides in the slag does not seem to represent a limit for the durability of concrete, due to their stabilization in crystalline lattice.