Eggshell powder as partial cement replacement and its effect on the workability and compressive strength of concrete

Concrete is the most preferred building material in the world and its production has increased exponentially with the rapid construction of infrastructures. The generation of waste materials has also increased due to rapid urbanization. Eggshell is one such solid waste material which is being generated in huge quantity due to it being a cheap source of nutrition. Cement, the vital ingredient of concrete has been reported to contribute approximately 7% of total global Carbon Dioxide (CO2) gas emissions. This experimental study was carried out to study the workability and compressive strength of M40 grade concrete incorporating Eggshell Powder (ESP) as supplementary cementitious material, to reduce the cement content in concrete. ESP was ground into two fineness (50 um and 100 um) and three different percentages (5%, 10% and 15% by weight of cement) of ESP was used to replace cement content. It was observed that partial cement replacement using ESP was successful in achieving higher strength compared to the control sample. It was determined that 10% ESP was optimum, where the highest compressive strength was achieved. Furthermore, the fineness of ESP also had an influence on the compressive strength, the ESP which passed 50 um resulted in better strength. The optimum ESP to be utilized was determined to be 10% in both fineness.