Enhancing performance and sustainability of cement mortar tiles with granite dust and marble powder

Abstract This study aims to develop sustainable two‐layer cement mortar tiles by incorporating industrial by‐products—granite dust (GD) as a fine aggregate replacement and marble powder (MP) as a partial cement substitute—and to optimize their composition for enhanced performance and reduced environmental impact. A factorial design with 12 mix formulations was used to evaluate the individual and combined effects of GD and MP on physical, mechanical, and durability properties. The results show that GD incorporation leads to improved matrix compactness, as evidenced by reduced water absorption (up to 66% at 15% replacement) and porosity (over 50% reduction). MP contributes additional improvements in density and strength. Based on macroscopic property correlations and established literature, these improvements are attributed to enhanced particle packing and the filler effect of the waste materials. The optimal mix (15% GD + 10% MP) achieved the highest bulk density (13.61 kN/m 3 ) and modulus of rupture (14.37 MPa). Multi‐objective Pareto optimization and regression modeling ( R 2 >0.90) confirmed the synergistic benefits of combining these materials. Furthermore, using MP reduced cement consumption by 10%, lowering the embodied CO₂ and improving the strength‐to‐carbon efficiency index. These findings demonstrate that GD and MP can be effectively used to produce high‐performance, eco‐friendly tiles suitable for residential and light commercial flooring, thereby supporting waste valorization and promoting sustainable construction practices.