EFFECT OF ADDITION OF NATURAL ADMIXTURE ON HYDRATION AND COMPRESSIVE STRENGTH OF CEMENT

Abstract

This research explores how the addition of a natural admixture influences the hydration process and compressive strength of cement mortar. Typically sourced from plants or minerals, natural admixtures are examined for their potential to modify and enhance the properties of cementitious materials, have gained attention as sustainable alternatives to chemical additives in construction materials. In this research, a selected natural admixture was blended with ordinary Portland cement mortar in varying proportions. The hydration process was monitored using standard techniques, while compressive strength was evaluated at different curing ages. Results indicate that the inclusion of the natural admixture influenced the rate of hydration and significantly affected the mechanical performance of the mortar. Optimal dosage levels were identified where improvements in compressive strength were observed without compromising workability. The findings highlight the potential of natural admixtures in enhancing the sustainability and performance of cement-based materials. In this study, the impact of incorporating a natural admixture at varying dosages on the compressive strength of cement mortar cubes was investigated. Results showed a consistent improvement in compressive strength with increasing admixture content, ranging from 1 ml to 5 ml. Compared to the control sample with no admixture, the strength enhancement varied from 1.46% to 18.07% at 28 days of curing and values range approximately from 24.64 (7days at 0 ML) to 55.62 (150 days at 5 ML) here is almost 5 MPa higher at 7 days and about 8.5 MPa higher at 28 days. Almost all ages, the 5 ml condition consistently yields higher strength than 0 ml. Results showed that increasing the admixture dosage led to a rise in both chemical shrinkage and hydration degree. Notably, the degree of hydration improved by 35.42% at a 4 mL dosage compared to the control sample without admixture. Correspondingly, cement mortar cubes (70.7 × 70.7 mm) exhibited a 10.84% increase in compressive strength at the same dosage. These findings suggest that the natural admixture positively contributes to hydration kinetics and mechanical performance.