Experimental Investigation and ANN Optimization of Cement Mortar Production Using Marble and Granite Waste Powder as Partial Cement Replacement

The study presents Experimental Investigation and ANN Optimization of Cement Mortar Production Using Marble and Granite Waste Powder as Partial Cement Replacement. For this purpose, a constant mixture of 50:50 granite and marble waste powder were used, and the cement was replaced by weight in various levels from 0 to 45%. Therefore, the entire work of mixing, testing, and curing the mortar specimens according to the appropriate ASTM standards proves the potential of granite and marble waste powder to improve the mechanical and durability performance of cement mortar under controlled laboratory conditions. Compressive strength and UPV were the two principal indicators of the mechanical performance. Nevertheless, the performance was also evaluated through durability-related characteristics such as sulfate attack resistance, porosity, and water absorption. The results of the experiments showed that the use of MGWP in the mixture of mortars of 15% or less resulted in water absorption and porosity being reduced. Besides, these properties were increased due to the better particle packing and matrix densification. The experimental optimum compressive strength of 33.9 MPa and maximum UPV of 4.1 km/s from the 10% this corresponds to an approximately 18% increase in compressive strength relative to the control mix (0% MGWP). This was confirmed by the specimens, which, when facing sulfate attack at the same replacement level, only lost 0.5 MPa and hence showed good resistance to sulfate attack. A Taguchi-based experimental design was adopted, which created a dataset to be used next in the development of an ANN model for performance prediction. The ANN predictions showed close agreement with experimental results, with a maximum prediction error of 2.65%. The optimal performance for this experiment achieved its peak at 10% MGWP replacement which produced a compressive strength of 33.9 MPa. The ANN model predicted 11.89% as the optimal replacement level which resulted in a compressive strength of 34.88 MPa that exceeded the experimental optimum by 2.8%. The integrated experimental and data-driven method shows that granite and marble waste powder can be used for creating eco-friendly cementitious materials with better mechanical and durability performance. Machine Learning-Driven Optimization of Cement Mortar Production Using Marble and Granite Waste Powder as Partial Cement Replacement