Multicriteria-based optimization and multi-variable non-linear regression analysis of concrete containing blends of nano date palm ash and eggshell powder as cementitious materials

Abstract The persistence of global concerns regarding the environmental effects of cement production, particularly its significant contribution to CO ₂ emissions, led to the search for different supplementary cementitious materials (SCMs). Hence, this research utilized date palm ash (DPA) as an SCM to produce concrete. Nano eggshell powder (NESP) was also incorporated as an additive to binder materials in the concrete to hasten the pozzolanic reaction in the concrete. DPA was used to replace between 0 and 40% of the cement by volume, and the NESP was added in dosage between 0 and 4% by weight of binders. Multi-criteria decision making (MCDM) technique was adopted by employing different methods that include MOORA and VIKOR to select the optimal mix proportions containing DPA and NESP. Furthermore, multi-variable non-linear regression (MNLR) analysis was used to develop mathematical models for predicting the concrete’s properties using the proportions of DPA and NESP as the variables. The findings from the MCDM showed that Mix M8 consistently ranked highest across both MOORA and VIKOR analyses, demonstrating superior performance due to optimal incorporation of 40% DPA and 2% NESP. The developed MNLR models attained high accuracy in predicting with good-to-excellent R ² values ranging between 0.79 and 0.94 for most properties.