Mechanical Properties of Concrete that Replace Cement Partly by Using Eggshell Powder

There are many problems due to the cement industry around the world besides the air pollution by greenhouse gas emissions. The issue occurs when a large amount of CO2 is released during the process of converting calcium carbonate lime (CaCO3) into calcium oxide lime (CaO), which is the primary component of cement. This transformation is made in an oven-dry by burning fossil fuels, in a process that releases more carbon dioxide. Substitute materials are usually industrial and municipal wastes .In this study, eggshell powder (ESP) are considered cementitious materials and were added to the cement at different percentages to reduce the cement contents in the concrete industry. Eggshell powder amounts of 0%, 5%, 10%, and 15% by weight were added as ordinary Portland cement (OPC) replacements. The advantages are associated with the high calcium content and good filling effect of eggshell powder. The curing ages were 7, 14, and 28 days. This study evaluates the fresh and hardened properties of concrete. Also, EDX and SEM analyses were conducted on the ESP and concrete to analyze the microstructure. Adding ESP accelerates the concrete setting time compared with the control mix. At the optimal content of 10%, ESC has various advantages compared to conventional concrete.