Properties of basalt fiber sulfo-aluminate modified cement binders

Brest State Technical University, 224017, Moskovskaya 267, Brest, Belarus

^* Corresponding author: pavlinna@tut.by

Abstract

The present paper considers the influence of basalt fiber method of addicting in to self-stressing concrete, modified by sulfoaluminate type expansive additive, on main properties of concrete. The use of basalt fiber and expansive additive together allows to obtain a composite with optimal structure and high-quality properties. The combined application allows to achieve several effects such as filling effect, pozzolanic effect and dispersed reinforcement effect (due to chaotic fiber distribution in the concrete composite structure and needle-shaped crystal of ettringite micro reinforcement). Use of even small amount of basalt fiber due to disintegration on a great amount of monofilaments with a great specific surface leads to an increase in concrete composite tensile strength due to spatial dispersed reinforcement effect and changing fracture toughness There is also an effect of simultaneous expansion due to adding an expansive additive and strengthening achieved by binding effect of basalt fiber as a dispersion-reinforcing element. The maximum amount of basalt fiber in the research is limited by 4% to prevent full percolation effect, but at the same time to provide the formation of filament spatial skeleton in the concrete structure. In this study are considered the changes of properties of the concrete composite with different degrees of expansion and self-stressing (varied by energy-activity and amount of sulfo-aluminate expansive additive). In the article the most optimal basalt fiber addicting method in the concrete mix is proposed, preferences and influence degree of this method on strength properties are determined. The integral use of the modifying expansive agent makes it possible to predict an increase in impermeability due to chemical-mechanical reinforcement of the structure, which results in durability of this type of concrete. This predetermines a perspective range of their applications in various kinds of structures including those with high serviceability.