Feasibility Study of Cockle Shell Powder as a Partial Cement Replacement in Mortar

The high demand for mortar in construction necessitates a significant amount of cement. Malaysia has eight cement manufacturers with an estimated production capacity of 40.2 million tonnes. However, natural depletion may occur during the mortar manufacturing process. Additionally, the disposal of seashell waste can negatively impact the environment and contribute to pollution, affecting human quality of life. This study aims to evaluate the feasibility of using marine waste, specifically cockle shell powder (CSP), as a partial replacement for cement in mortar mixtures. The properties of mortar containing varying percentages of CSP (3%, 6%, 9%, and 12%) as a partial cement replacement were investigated. The effects of CSP on workability, compressive strength, and water absorption were analyzed. The findings indicate that the optimum CSP replacement level is 6%, as its properties closely match those of the control mortar, making it an excellent candidate for substitution. However, the experimental results also show that incorporating CSP as a partial cement replacement reduces the workability and strength of the mortar specimens. Furthermore, an increase in CSP percentage corresponds with higher water absorption.