Optimizing Cement Performance: Evaluating Chemical and Mechanical Properties through Blending OPC with Mustard Husk Ash, Silica Fume, and Gypsum

Abstract A model proposed in this paper in which OPC is blended with agro-waste MHA, industrial waste SF, and GS. We proposed various experiments to study its chemical as well as mechanical properties. Gypsum (GS), which acts as a retarder for setting time, the optimal amount of gypsum used is 3%. In comparison, MHA-blended OPC has a shorter initial setting time than OPC, but when GS and SF are added in a fixed proportion, the setting time increases. However, beyond a mix ratio, the setting time starts to decrease. The concentration of calcium ions is higher in MHA-blended OPC and lower in MHA-SF and GS-blended OPC due to the pozzolanic reaction between MHA and SF. The formation of C-S-H (calcium silicate hydrate) is greater in MHA, SF, and GS blended OPC, which enhances the strength of the cement. SEM images confirm that there is more C-S-H form in OPC12MHA10SF3GS after 28 days of hydration, resulting in 30% more strength compared to control OPC. OPC12MHA10SF3GS is a better cement than control OPC in physical and mechanical aspects. The use of MHA utilises huge amounts of agro-waste and decreases the production of OPC. This is very beneficial for environmental conservation and also helps to reduce the cost of cement.