Mechanical properties of concrete pavements containing combinations of waste marble and granite powders

The ornamental stone industries in Iran produce vast amounts of waste by-products that cause significant environmental impacts. Granite and marble which are among these by-products can be used in different productions. The primary goal of this study is to experimentally investigate the effects of using these recycled aggregates as substitutes for natural fine aggregates on major mechanical properties of concrete pavements. Different mixes were prepared with variable contents of granite and marble powders, and are compared on the basis of their compressive strength, abrasion resistance, modulus of rupture, splitting tensile strength, and Young's modulus of elasticity. Percentage of waste powders in the specimens ranged between 10 and 30% for a single marble or granite substitution and between 7.5 and 22.5% for the compound substitution. The results show that the mechanical strength decreases with the increase in marble content, but increases with the increase in granite content. The results encourage utilising a combination of marble and granite powders in concrete production. This reuse can help to mitigate the environmental effects of these by-products while producing compound concretes with the same or improved mechanical properties.