Assessment of engineering properties and durability of concrete using steel slag as coarse aggregate

Abstract

Steel slag (SS) is an industrial by-product, which is considered a potential material for replacing natural aggregates in concrete to limit the exploitation of natural resources and minimize the impact on the environment during the SS treatment. This study investigated the potential of re-using locally available SS as coarse aggregate in concrete and then evaluated the influence of different SS replacement levels for natural coarse aggregates on both fresh (i.e., workability and unit weight) and hardened properties (i.e., porosity, compressive strength, flexural strength, ultrasonic pulse velocity, surface electrical resistivity, water absorption, and dry shrinkage) of concrete. Experimental results show that replacing 40–100% (by volume) natural coarse aggregate with SS reduced workability and increased the unit weight of the fresh concrete mixture. Although the concrete porosity, water absorption, and drying shrinkage increased with increasing the SS content, the mechanical strength of the concrete was improved. Besides, the concrete samples containing SS exhibited an enhancement in surface electrical resistivity and their ultrasonic pulse velocity was comparable to that of the SS-free sample. The experimental results further demonstrated the high potential of utilizing SS as coarse aggregate in the production of concrete for sustainable development in construction.

Keywords

• concrete
• steel slag
• coarse aggregate
• workability
• durability