Development of durable engineered cementitious composites using local ingredients

Abstract

Environmental and economic concerns impel large volume construction materials to employ as many local ingredients as feasible while maintaining high performance. In this research, durable Engineered Cementitious Composites (ECC) are developed using local desert sand from Saudi Arabia, polypropylene/polyethylene fibers, and crystalline admixture. Multi-scale characterization methods were utilized, including compressive/uniaxial tensile tests, self-healing tests, permeability tests, and micro/chemical analyses. Mercury intrusion porosimetry, X-ray diffraction, and scanning electron microscopy were employed to interpret the mechanisms underlying the observed macroscopic behavior. The developed ECC possesses the highest ductility (8.6 %) and lowest crack width (below 63 μm) among desert sand ECCs in the literature. The crystalline admixture produces additional C-S-H gel and crystalline Ca(OH)2 precipitates, endowing the desert sand ECC with enhanced self-healing ability. The self-healed ECC demonstrates improved durability with reduced permeability and enhanced mechanical properties recovery. The localized durable ECC holds promise for both rehabilitating aging infrastructures and newly constructed facilities in regions with large supplies of desert sand.