МНОГОКОМПОНЕНТНОСТЬ – ОСНОВНОЙ ФАКТОР ФОРМИРОВАНИЯ СТРУКТУРЫ И СВОЙСТВ ВЫСОКОПРОЧНЫХ БЕТОНОВ

Abstract

The prospects and problems of multicomponent multilevel optimization of the dispersed composition of self-compacting concrete are considered with the aim of significantly increasing its construction and technical properties, with a minimum content of binder. Theoretical and practical principles have been developed for the design of disperse-particle size distribution of self-compacting concrete mixtures for high-strength concrete, in which various types of dispersed mineral modifiers (MM) are used, including fly ash of thermal power plants. Effective MMs for self-compacting concrete mixtures are differently dispersed granular blast furnace slag, fly ash of thermal power plants and silica fume, which create a dense packing structure of particles of a multicomponent binder with a low degree of disorder and ensure a decrease in the consumption of Portland cement in concrete up to 50% and higher. With such a choice of the type and parameters of MM, self-compacting concrete mixtures are characterized by lower water content, high viscosity and a low level of ultimate shear stress, ensuring its high-quality compaction. To study the properties and structure of concrete, quartz sand with Mk -2.58, granite crushed stone fr. 5-10 mm, Portland cement of class CEM I 52.5 N, finely dispersed granulated blast furnace slag, fly ash of thermal power plants, micro-silica and superplasticizer Glenium 430. For a uniform course of the pozzolanic reaction, a finely dispersed cement fraction was used in each micro-volume. Research methods: the shape and size of the dispersed particles of the components were determined by a laser analyzer, the mobility of the concrete mix in accordance with GOST 10181-2014, the compressive strength of concrete in accordance with GOST 10180-2012. The structure of the cement stone was studied by thermographic and X-ray phase analysis methods.