Enhancing the permeability and abrasion resistance of concrete using colloidal nano-SiO2 oxide and spraying nanosilicon practices

By protecting concrete from penetration of aggressive chemicals, low permeability is one of the most important contributory factors to the concrete's durability. In this paper the effects of nano-SiO2 particles on concrete permeability are studied through employing the technique of spraying nanosilicon and treatment in the water-diluted nano-SiO2 oxide. To this end, some mechanical and microstructure properties of concrete are investigated. The results show that the compression strength and the resistance of specimens to water penetration are significantly increased, whether in the mixtures cured in the colloidal solution or those being sprayed with nano-SiO2. The minute dimensions of these particles allow them to penetrate up to a particular depth in a concrete panel. Hence, through improvement of concrete panel nanostructures, these particles participate in the completion of the hydration process, which in turn leads to a reduction in their permeability and development of a protective layer, and therefore the increase of bulk concrete panel durability. The experiment's outcomes also develop thorough understanding of the effects of nano-SiO2 as an additive material after preparing the concrete and during the curing process. (C) 2017 Elsevier Ltd. All rights reserved.