Use of Alternative Limestone Fillers as Sand Replacement in Mortars

Limestone fillers are increasingly recognized as a sustainable alternative to cement and sand in mortar and concrete mixtures, driven by environmental concerns over the excessive use of natural resources and raw materials. This study investigates the potential exploitation of different limestone fillers, waste products of the quarrying industry, in the production of cementitious composites. The investigation includes the physico-mechanical characterization of a number of mixtures with different percentages of limestone fillers used as partial replacement to sand. The results show that increasing the limestone filler content negatively influences the mechanical performance of the hardened end-products, decreases their density and increases their open porosity. At the same time, increased clay particle content in the limestone filler decreases the workability of the fresh mixtures.