Environmental and Economic Benefits of Eggshell Powder as a Cement Alternative in Concrete

Since cement production contributes to the world's CO2 emission, increased awareness of environmental concerns has driven research into greener alternatives for concrete. This paper considers eggshell powder, a waste from egg processing industries, as a supplementary cementitious material. Compressive strength tests, flexural strength, split tensile strength, workability, and durability of concrete mixed with various dosages of ESP at 0%, 5%, 10%, and 15% have been conducted after 28 days of curing. The addition of 5% ESP increased the compressive strength of concrete by 19.3% compared to the controlled mixture. Furthermore, ESP positively affected the mixes' split tensile strength and workability. Such an improvement in the properties of concrete was because of the pozzolanic reaction between ESP and Ca (OH)₂ in cement hydration, thus improving the interfacial bond between the cement paste and the aggregates. These findings suggest that ESP is a promising, greener alternative to traditional Portland cement, which would be environmentally and economically advantageous because of the reduced carbon footprint in concrete production.