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<p>Using the method of dynamic light scattering we investigated the influence of the rotor and pulse impact on a dimensional change of particles in calcium chloride hydrosol used as texturing additives in concrete mixing. The mechanism of the strengthening action of the additive is shown by the results of an assessment of the parameters of the pore structure of the cement stone which is carried out by the method of the low-temperature adsorption and desorption of nitrogen vapors. With the use of the method of the low-temperature adsorption desorption of nitrogen for the analysis of porosity of the experimental exemplars of the cement stone received with the use of the mechanically activated CaCl₂ solution, decrease in the area of a specific surface area in 1.7 … 2.1 times and the volume of pore spaces by 1.6 times that is caused by preferred decrease of the maintenance with the diameter over 6 nanometers and decrease in an upper bound of pore size from 160 to 90 nanometers is shown.</p>

The possibility of obtaining tinted glazes without the synthesis of iron-bearing pigments is considered. Fine particles of an iron-based alloy, for instance steel obtained by fine milling of metal working waste, are introduced in the glaze composition. The testing of a glaze suspension based on window glass cullet with additives of white-burning clays and finely milled carbon steel chips demonstrate that this suspension after firing yields a uniformly tinted coating.Glazing of articles made of various inorganic materials is finding ever increasing applications. Apart from glazing of traditional ceramics, various technologies for glazing concrete products have been developed. Unlike ceramics, concrete items cannot be completely placed into a firing furnace due to the presence of hydrate water in cement stone. It is proposed to fire glaze on concrete using screen furnaces or the induction discharge flame of a gas burner [1,2].Glazing of ceramics and nonfired materials uses various colorant pigments, including those containing F 2 O 3 as a chromophore. It is known that the maximum effect in the formation of a tint depends on the electromagnetic radiation absorption spectrum, which is a light flux due to the electron transfer between the chromophore ion and oxygen, i.e., the emergence of charge transfer bands [3]. The emergence of color bands is related to photon absorption due to a charge transfer with the transition of an electron from the oxygen ion to the central ion (usually a transition element, such as Fe, Mn, Cr, Co, Ti, etc.), the transition of an electron from ions of the same metal in different valence states in theiretc.), and the formation of redox complexes with ions of different variable-valence metals (Fe 3+ -O 2--Mn 2+ , Mn 4+ -O 2--Fe 2+ , Ti 4+ -O 2--Fe 2+ , Mn 4+ -O 2--Ti 3+ ) [3].The presence of these elements in a glaze contributes to a better chemical interaction between the glaze layer and the article surface (due to ion substitution) and the emergence of a transition layer.It is advisable to use variable-valence metals (iron, cobalt, nickel, chromium, manganese, etc.) as colorant components in glazes for nonfired materials, since they have a high tinting capacity and a favorable effect on the physicochemical properties of glazes intended for deposition on nonfired materials. The most preferable compounds are oxides, but other compounds are possible as well, such as sulfides, sulfates, chlorides, nitrates, and also microparticles of some metals [4]. Tinted metal compounds can be introduced directly in a raw glaze batch or in frit melting.At the same time, tinted glazes can be obtained as well without synthesizing relatively expensive iron-bearing pigments.In this study it is proposed to introduce Fe 2 O 3 for glaze tinting in the form of fine particles of iron-based alloys, for instance, steel particles produced by fine milling of metal working waste (chips, filings, etc.) [5]. Standard carbonbearing steel contains (here and elsewhere, wt.%): 0.06 -0.62 carbon, 0.25 -0.90 manganese, not more t...

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Despite the major advances in ensuring fire safety of buildings and structures, fire risks still represent the serious issue not only on the territory of the Russian Federation but on the global basis. Presently, while erecting buildings and structures focused attention is given to lowering material consumption and reducing construction time. This is achieved by means of application of lightweight building envelopes with efficient insulators. For the most part, foam poly styrene plates are used as an insulator. Expanded or foam poly styrene has low coefficient of heat conductivity, high acoustic isolation, long-term durability, moisture resistance, and is characterized by ease of installation. However, application of foam poly styrene has constrains due to its high contribution to the propagation of fire. In the present paper, the authors proposed new flame-retardant composition on the base of organo-siloxanes, which inhibits combustion initiating of foam poly styrene and constrains fire propagation when applied on the surface of foam poly styrene plates.

Abstract. For Russia, due to its long winter period, improvement of thermal insulation properties of envelope structures by applying thermal insulation paint and varnish coating to its inner surface is considered perspective. Thermal insulation properties of such coatings are provided by adding aluminosilicate microspheres and aluminum pigment to their composition. This study was focused on defining the effect of hollow aluminosilicate microspheres and aluminum pigment on the paint thermal insulation coating based on water-based polymer dispersion and on its optimum filling ratio. The optimum filling ratio was determined using the method of critical pigment volume concentration (CPVC). The optimum filling ratio was found equal to 55%.

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The present paper deals with modifying composition of plastering mortar for the purpose of enhancing fire resistance of building structures by means of silicate additives. Interaction of soluble water glass with cement binder elongates the initiation of setting time and reduces the time of final setting that could be explained by the opposed action of each component. One of the components facilitates the increase in the mobility of the mortar while the other, as opposed, is fastening rapidly. The optimum choice of the mixing ratio in the mortar would enhance both physical-mechanical and thermal properties.