Abstract
The construction industry faces mounting pressure to develop sustainable alternatives that maintain structural performance while reducing the environmental impact. This study investigates the potential of crushed dune sand (CDS) as a partial cement replacement in high-performance concrete (HPC) formulations. Desert regions possess abundant dune sand resources that, when mechanically processed, can serve as supplementary cementitious materials with minimal environmental footprint. The research examined concrete mixtures incorporating CDS and silica fume at replacement levels of 5, 10, and 15% by weight of cement. Comprehensive testing protocols evaluated fresh concrete properties, mechanical performance, durability characteristics, and microstructural development using scanning electron microscopy and X-ray diffraction analysis. Nondestructive testing methods including sclerometer measurements and ultrasonic pulse velocity (UPV) validated the experimental findings. Results demonstrated that 10% cement replacement with CDS achieved optimal performance, yielding 58.03 MPa compressive strength at 28 days compared to 52.1 MPa for reference concrete, representing an 11.4% improvement. Water-accessible porosity decreased from 8.1 to 7.2%, indicating enhanced durability potential. UPV increased by 12%, confirming improved material density and reduced void content. Environmental analysis revealed that CDS exhibits carbon dioxide emissions of only 0.0013 kg per kilogram of material and energy consumption of 0.017 MJ/kg, substantially lower than conventional supplementary materials. Microstructural examination confirmed that CDS enhances concrete through combined physical filler effects and pozzolanic reactions, creating denser interfacial transition zones and additional calcium silicate hydrate formation. The findings establish CDS as a viable, sustainable alternative for HPC production in arid regions, offering superior mechanical properties, enhanced durability, and significant environmental benefits compared to conventional approaches.