Optimizing properties of concrete containing stone dust and ceramic tile: a response surface methodology approach

The construction boom of the 21st century has heightened demand for natural aggregates, leading to significant environmental degradation worldwide. On the contrary, there is a substantial generation of industrial waste and by-products like ceramic tile waste and stone dust, which are merely disposed of and stored in landfills. While both materials have the potential to be viable alternatives to natural aggregate in concrete production, their combined effects on concrete remain unexplored. This study aims to predict and optimize concrete properties incorporating stone dust (SD) and ceramic tile aggregate (CTA) as partial replacements for natural fine and coarse aggregates, respectively. Regression models were developed using response surface methodology (RSM) to assess the physical (fresh density and slump), mechanical (compressive strength, splitting tensile strength and bond strength) and durability (water absorption and carbonation depth) properties of concrete, with volumetric percentages of SD and CTA as independent variables. The analysis of variance (ANOVA) for all the desired responses indicated that the developed regression models were statistically significant in predicting the concrete properties. Based on multi-objective optimization, optimal replacement proportions of CTA and SD for enhanced concrete properties were obtained to be 30% and 30.867%, respectively. Hence, our findings highlight the insights of utilizing CTA and SD as viable substitutes for natural aggregate, offering a practical pathway to sustainable concrete production.