Optimization of production variables for metakaolin and rice husk ash-based geopolymer cement

Abstract

Geopolymer concrete has emerged as an eco-friendly alternative to conventional Portland cement-based concrete, boasting superior mechanical performance and a significantly reduced carbon footprint. This research delves into the effects of incorporating rice husk (RH) and metakaolin (MK) as supplementary materials in geopolymer concrete, with the goal of enhancing its properties and sustainability while making productive use of industrial by-products. The research commences with a comprehensive characterization of the raw materials, including rice husk ash (RHA) and metakaolin, via physical, chemical, and mineralogical analyses. Different combinations of RH and MK are then blended with an alkali activator solution to formulate geopolymer paste mixtures. The findings of this study reveal that the incorporation of RH and MK as partial substitutes for conventional materials in geopolymer concrete yields positive effects on its performance. The utilization of rice husk ash enhances workability and reduces the alkaline activation time of the geopolymer paste, leading to improved early-age strength development. This study demonstrates that the synergistic use of rice husk and metakaolin in geopolymer concrete promotes a more sustainable construction material with a diminished environmental impact. It offers valuable potential to guide engineers, researchers, and industry professionals in adopting sustainable and cost-effective strategies for enhancing the properties of geopolymer concrete, thus fostering its wider adoption in the construction sector.