Effect of Waste Marble Powder and Micronized Calcite on Hydration Kinetics, Phase Assemblage, and Mechanical Performance of White Portland Cement

Abstract

This study investigates the potential usage of waste marble powder as a sustainable alternative for commercially produced micronized calcite. Even though CaCO ₃ itself does not exhibit pozzolanic or hydraulic reactivity, when it is used in a highly micronized form, it can still enhance the system by acting as an efficient filler and promoting the nucleation and growth of hydration products. To clarify the mechanism and determine the optimum substitution level, white OPC was partially replaced with different CaCO ₃ – based materials at substitution ratios of 10% and 20%. CIE Lab whiteness analysis was performed to check the whiteness of the blend systems. Isothermal calorimeter analysis was conducted to observe the hydration behavior. The evolution of the blended systems was monitored by X‐ray diffraction (XRD) at curing ages of 2, 7, and 28 days. Compressive and flexural strength tests were performed to assess mechanical performance at both early and later curing ages. The results highlight the potential of waste marble powder as a sustainable and cost‐effective alternative to commercial micronized calcite. Its utilization promotes the valorization of industrial by‐products, supports circular economy principles, and contributes to the sustainability of white cement products. Furthermore, waste marble powder exhibited performance comparable to that of micronized calcite, demonstrating its technical feasibility as a clinker‐reducing constituent in white cementitious systems.