Performance optimization of Water-Cooled Slag-Metakaolin Geopolymer Composites with polypropylene Fiber Reinforcement

The growing demand for innovation and carbon dioxide reduction in the civil construction sector has accelerated interest in eco-friendly and sustainable alternatives to traditional binding materials, such as geopolymer concrete. This study investigates the enhancement of Water-Cooled Slag-Metakaolin (WCS-MK) geopolymer composites with polypropylene (PP) fibers to address traditional geopolymer drawbacks, such as high shrinkage and brittleness. Using a mixture of 10% NaOH and 10% Na2SiO3 as an alkaline activator, PP fibers were added incrementally up to 2% by weight. The results demonstrated a 21% increase in compressive strength with the optimal addition of 1% PP fiber, alongside a significant reduction in drying shrinkage. The incorporation of PP fibers not only improved the ductility of the composites but also facilitated effective void management, as confirmed by SEM analysis. XRD analysis further revealed enhanced mineralogical phases, contributing to improved morphological properties. This study highlights the potential of fiber-reinforced geopolymer composites as a sustainable solution with improved mechanical and durability characteristics, offering promising applications in eco-friendly construction and repair work.