Experimental Study on Partial Replacement of Fine Aggregate with Quarry Dust

The increasing demand for concrete and exhaustion of natural sand materials are the reasons to seek sustainable sources in construction materials. Quarry dust, being a by-product of stone crushing units, is an underutilized material that has the potential to serve as a partial substitute for fine aggregate in concrete. This experimental research compares the workability and mechanical properties of concrete when natural fine aggregate is partially replaced with 10%, 20%, and 30% by weight quarry dust. Concrete mixes were created using the standard M20 grade proportions. Workability was assessed through slump tests, while compressive strength was examined at curing ages of 7, 14, and 28 days. The results reveal a decrease in workability as higher quarry dust content was added, due to the angularity and finer particle size of the dust. The mechanical properties, however, showed improvement up to 20% replacement, wherein compressive strength increased by around 8–12% over the control mix. At above 20%, strength gains were levelled or declined slightly, an indication of optimal replacement percentage. This research verifies that quarry dust can act as an effective partial replacement for fine aggregate, especially at 20%, and has economic and environmental advantages. The use of quarry dust not only minimizes the use of river sand but also aids in the sustainable management of construction industrial waste.