Preparation and characterization of basalt fabrics coated with zirconia obtained by sol-gel method for textile reinforced concrete

Abstract

The poor alkali resistance of basalt fabric greatly affects the mechanical properties of textile reinforced concrete. In this study, dense zirconia coating obtained by sol-gel method was coated on the basalt fabrics surface as additional sizing to improve the alkali resistance of basalt fabrics. The morphology, wettability and phase composition of the fabric surfaces was characterized by scanning electron microscopy (SEM), static water contact angle (SWCA), X-ray powder diffraction (XRD), fourier transform infrared spectra (FI-IR), X-ray photoelectron spectroscopy (XPS) and Raman. The tensile properties of various basalt fabrics immersed in alkaline solution for different time and the mechanical property of concrete composites were examined by universal material testing machine. Results showed that a protective membrane was formed on the surface of basalt fabrics to prevent the diffusion of hydroxide ions. The final strength retention ratio of BF-c-ZrO2 (Basalt fabric-coated-Zirconia) fabrics could maintain at 89.92% compared with that of pristine basalt fabrics, which reached below 40%. The compressive strength and flexural strength of BF-c-ZrO2 fabrics reinforced concrete increased by 10.15% and 19.0% compared with that of pristine basalt fabrics reinforced concrete. A theoretical model was proposed to predict the ultimate flexural bearing capacity of BF-c-ZrO2 fabric reinforced concrete based on the equivalent stress rectangle theory. The corresponding predicted value compared with experimental result indicated a good coincidence and a reasonable accuracy, which was less than 5% of their discrepancy.