THE EFFECTS OF NANO SIO2 AND SILICA FUME ON THE ENGINEERING PROPERTIES OF CEMENT CONCRETE IN CONSTRUCTION, VIETNAM

Abstract

This work aims to study the effects of Nano SiO2 (NS) and Silica fume (SF) on the technical parameters of cement concrete. On specimens with varying NS and/or SF concentrations, compressive strength, flexural strength, abrasion resistance, elastic modulus, and chloride ion penetration were tested. All specimens were subjected to the proposed method/technique cured at the ages of 3, 7, 28, and 60 days with a temperature of 25 ± 2°C and relative humidity of above 90%. NS particles were added to cement concrete at various replacements of 0, 0.5, 1.0, 1.5, and 2.0% by the mass of the binder. The water/binder ratio remained at 0.37 for all mixes. Then, for cement-concrete were prepared 45 MPa (C45) with NS and SF. The specimens confirmed the new method of effectiveness evaluation. The specimens were prepared under two different categories: (1) Portland cement replacement with NS of 0%, 0.5%, 1.0%, 1.5%, and 2.0%, by weight for adhesives; (2) Portland cement replacement with NS of 0.5%, 1.0% and each NS content in combination with SF of 5%, 10%, and 15%, respectively, by weight for adhesives. The values for abrasion resistance and Chloride Ion penetration are the smallest value. Finally, an analytical model for forecasting elastic modulus and flexural compressive strength of cement concrete was created using the collected data. In the future, it should help us better comprehend cement concrete utilizing SN and SF.