An Experimental Investigation of the Effects of Steel slag with Metakaolin by Partial Replacement of Cement to Increase the Mechanical Properties of Concrete

This work investigates the use of steel slag powder as a filler in metakaolin-based geopolymers (MGP) to enhance concrete's mechanical properties. The work aims to recycle steel slag waste as a supplementary ingredient in MGP, creating a new geopolymer composite. Key findings indicate that MGP improves concrete strength, especially during the early curing stages, and that steel slag can effectively replace a portion of cement, resulting in enhanced volume stability and reduced drying shrinkage. The study also highlights that using moist curing significantly benefits the mechanical properties of steel slag modified geopolymer (SSMG). In comparison to MGP, this design results in an 8% improvement in bending strength without changing compressive strength. Additionally, the study shows that interactions between metakaolin and steel slag alter the micro-morphology and crystal structure, which enhances the strength of SSMG. Metakaolin-based geopolymer composite (MGC) and steel slag-metakaolin-based geopolymer composite (SSMGC) are compared in the experimental results; SSMGC finally demonstrates strength advantages despite poorer early-age performance. Steel slag (SS) has an impact on concrete strength as well; MK is especially useful for early curing. All things considered, this study encourages the sustainable recycling of steel slag in construction, providing substantial advancements in concrete technology to prevent common structural failures associated with cracking. For example, 0%, 4%, 6%, 8% and 0%, 4%, 6%, 6% of the materials used in the mixing process are metakaolin and steel slag, respectively.