The effect of eggshells powder as cement substitute material in self-compacting concrete on compressive and tensile strengths.

The decreasing availability of masons led to the need for self-compacting concrete mixture in the construction site. It only requires a few masons, but it can create high-quality concrete. The concrete makes use of the aggregate size setting, aggregate portion, and superplasticizer admixture to obtain a special thickness that allows the concrete to flow independently without the aid of a compactor. The use of substitutes for cement in concrete mixture has been widely practiced, both organic and inorganic waste materials. One of the many organic wastes that we can easily find in Indonesia is eggshell waste. The objective of the research is the effect of eggshells as a cement substitution material in Self-Compacting Concrete (SCC) on compressive strength and tensile strength value with 0%, 2.5%, 7.5%, 12.5%, and 17.5% variations. The research method used in this research was an experimental method which was carried out at the Laboratory of Building Material, Structure, and Construction, of the Department of Architecture, Universitas Hasanuddin. Quantitative research with experimental based on two variables (age and concrete treatment) was also used as the research method. The data was obtained from the test specimen by measuring the compressive strength and tensile value of the concrete with a Universal Testing Machine (UTM). The data analysis method used in the research was comparative analysis by using tabulations and charts. The results showed that the effect of eggshell substitution or ESP (eggshell powder) on 28-days-old SCC could increase the concrete compressive strength even though it was not optimal. While the tensile strength shows higher value strength than SCC variation 0% (normal SCC). [ABSTRACT FROM AUTHOR]