Structural Performance of Concrete mixed with Gum Arabic as a Biopolymer Admixture and Calcined Kaolin as a Partial Replacement for Cement

Abstract

The goal of this study focuses on the influence of gum Arabic as a biopolymer admixture on setting time, Workability, and mechanical properties of concrete mixed with calcined kaolin. Concrete was mixed with calcined kaolin (CK) in the proportion of 0%-30% by cement weight and cured under laboratory conditions for 28 days. Later gum Arabic was added to the concrete at the following ratios 0%-1% after obtaining the optimum percentage of calcined kaolin. The addition of gum Arabic in concrete delayed the initial and final time, improved the Workability, and increased the mechanical properties of concrete. Furthermore, an SEM test was performed on cement, calcined kaolin, and gum Arabic in powder form to study their surface morphology. Gum Arabic was added to the cement mixture and calcined kaolin in powder form and was subjected to X-ray fluorescence to analyse its chemical compositions. Finally, the study concluded that 20%CK was the optimum since the compressive strength was above the minimum value required at 28 days due to the silicon content in CK that could react with lime in cement compared to 25% and 30%. Also, 0.8%GAB was the percentage whereby concrete reached its high compressive strength