Effect of graphene and basalt fibers on water penetration resistance of manufactured sand mortar

Abstract

This study employed water permeability and storage tests to investigate the effects of graphene and basalt fibers on the resistance to water penetration in mortar prepared with manufactured sand. The mineral composition and microstructural morphology of the materials were characterized through techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and pore analysis. The underlying mechanisms were analyzed alongside workability, mechanical properties, and shrinkage tests. The results demonstrate that the incorporation of graphene and basalt fibers significantly enhances the mechanical properties and water penetration resistance of the mortar while simultaneously reducing its natural shrinkage and optimizing pore distribution, thereby reducing pore connectivity. When the graphene dosage was 0.02 % and the basalt fiber dosage was 0.5 %, the compressive strength at 28 days increased by 7.61 % compared to the control group, while the water penetration height decreased by 71.56 %. Additionally, shrinkage was reduced by 55.8 %, the pore spacing factor increased by 39.6 %, and the air content decreased by 46.8 %. No cracking or leakage was observed at the bottom of the mortar specimens after 48 h of water storage. The addition of graphene and basalt fibers promotes the formation of cement hydration products, reduces microcracks, and increases the density of the matrix, ultimately enhancing the resistance to water penetration of the mortar containing graphene and basalt fibers.