Cladding of buildings and structures, combining decorative, protective and thermal insulation functions, is currently in great demand in the construction industry. One of the effective areas for using vitreous and glass-crystalline enamel coat-ings is the protection of steel cladding panels for construction purposes. Therefore, there is a need to create and widely implement competitive enamel-coated panels made in Russia with specified properties. The work identifies the areas of glass formation and constructs a composition diagram in the SiO2–B2O3–Na2O–RxOy system of glass areas, which are the basis for the production of ground and top enamels. The physicochemical patterns of glass formation in the Na2O–B2O3–Al2O3–SiO2–RxOy system for the production of enamel coatings have been established by varying the values of the connectivity indicators of the aluminum-boron-silicon-oxygen framework.

The purpose of these studies is to determine the possibility of using drill cuttings from the oil fields of the Southern Fed-eral District as a source for the production of ceramic ordinary bricks with their maximum content in the initial mixture to take into account their physical and chemical properties. The objects of study were: drill cuttings from the Slavyanskoye oil field (Krasnodar region) and clay (VKV-2) from of the Vladimirskiy quarry (Rostov region). Based on the research results, a working hypothesis has been formulated, which is that complex processing of the composition of the mineral component of drilling waste and plastic clay at the stages of preparation, molding, and drying ensures, under low-temperature firing conditions, compliance of the physical and chemical properties of brick with the requirements of GOST 530–2018 and their preservation during long-term operation

The article discusses the production of calcium-aluminoferrite clinker (cement) from a three-component mixture (by sin-tering), where 56.2-57.4 wt.% of the mixture consists of aluminum– and iron-containing man-made waste. It was found that the use of man-made waste as a component of the raw material mixture leads to a decrease in the amount of waste generat-ed by 4.9-5.4%, based on the production of 300,000 tons of calcium-alumoferrite cement per year. The results of qualitative and quantitative X–ray phase analysis of the clinkers obtained are presented, which indicate the formation of calcium aluminates (CA,C3A,C12A7), calcium aluminoferrite(Ca2(Al,Fe)2O5) and calcium silicate (α-, β-C2S) as the main clinker phases in all samples. Clinker phases of aluminate and calcium aluminoferrite are formed not in pure form, but with the introduction of impurity elements (Mg2+, Ti4+). Determination of the hydration activity of CAFC showed that the quantitative ratio of clinker phases CA:Ca2(Al,Fe)2O5 = 38.8:33.8 (CAFC I) and CA:Ca2(Al,Fe)2O5 = 27.6:23.9 (CAFC II) leads to an increase in the strength of cement stone in the initial periods of hardening by 48 and 32 MPa, and in later periods (28 days) - to an increase in strength by 28 and 8 MPa, respectively.

Ensuring high water resistance, frost resistance and corrosion resistance of hydraulic structures is achieved by creating concrete with a dense structure that can absorb aggressive influences. This is possible by modifying the structure of concrete with polymer additives of new generation. The introduction of polymer additives has a plasticizing effect and contributes to the preservation of technological properties of the concrete mixture, modifies the pore structure of concrete and influences the formation of cement stone strength. The paper presents the results of research on the effect of polymer additive based on polyvinylpyrrolidone on the basic properties of Portland cement binder. It was found that the compressive strength at the age of 2 days increases by 7% at the content of polymer additive in the amount of 0.8%. Also, in-troduction of polymer additive increases the compressive strength at the age of 28 days at its content of 0.6 and 0.8% by 22 and 27%, respectively. The effect of polymer modifier on the formation of the initial structure, manifested in the increase in the time of the beginning and accel-eration of the end of setting has been established. The kinetics of heat release of cement dough in the presence of polymeric modifier in the amount of 0.6 % has been studied. The data on the phase composition of cement stone in the presence of polymer modifier are given. It is established by means of electron microscopic analysis that the introduction of polymeric admixture promotes modification of cement stone microstructure with formation of more dense homogeneous structure. The given research results are taken into account in the development of concrete compositions with a set of specified properties required for the construction of hydraulic structures.

The mechanism of structure formation during hydration of duodecalcium semialuminate in the presence of plasticizer is considered. The purpose of the study was to determine the influence of polycarboxylate-based plasticizer on the formation and morphology of the hydrate phases formed. The object of the study was the mineral duodecalcium semialuminate 12CaO-7Al2O3 of stable α-form, having cubic syngony and plasticizer on polycarboxylate basis. The structure of cement stone was studied using X-ray phase and electron microscopic analysis. The mechanism of structure formation during hydration of duodecalcium semialuminate 12CaO∙7Al2O3 in the presence of plasticizer is presented, which consists in the formation of finely dispersed poorly crystallized hexagonal crystals of calcium hydroaluminate. The presence of superplasticizer in the composition of hydrated calcium aluminate slows down the nucleation and growth of crystalline hydrates due to the film formed on the surface of the interface between liquid and solid phases, creating a structural and mechanical barrier, which leads to slower saturation of the liquid phase, but promotes the formation of a greater number of crystallization centers and simultaneous growth of small crystals of both hexagonal and cubic habitus.

To date, the issue of handling toxic unsorted waste of cathode ray tubes (CRT) glass cullet remains relevant. The present paper proposes to replace part of the fine aggregate of cellular concrete intended for sound, heat or radiation protection with CRT glass waste heat-treated in the presence of a sodium hydroxide solution. The purpose of the research is to study the structure formation of the cellular concrete pores in case of replacement of part of the aggregate. The microscopy of the samples fracture was studied both visually and using software that made it possible to estimate the pore size when convert-ing the image to the relief mode. The study showed that the aggregate replacement results not only in quantitative changes in pore size, but also in qualitative changes related to the mechanism of the pore structure formation. Thus, when adding unsorted waste heat-treated in an alkaline environment, with a particle diameter of no more than 630 μm, there was a decrease in pore size and a decrease in size distribution compared with the reference sample. The changes are caused by structure formation, which can be divided into two stages - the formation of conglomerates and their swelling. With a decrease in the diameter of the part of the waste of a maximum size of 90 μm, a decrease in the pore size was recorded compared to the reference value, but due to the concrete skeleton formation before the end of gas development, destruction of the pore walls was observed.

The paper describes a one-component cement-silicate paint based on white Portland cement and sodium hydrosilicate, which lacks expensive zinc oxide and potassium liquid glass. The paint is supposed to be produced as a dry mixture, which can be applied in the conditions of the construction area using mixers. It is shown that the introduction of chrysotile nano-fibers into the basic composition of the paint allows its use for painting hot surfaces operating at temperatures up to 700 ºC. The use of nanodispersed titanium dioxide in the composition of cement-silicate paint provides self-cleaning of the painted coating due to photocatalytic reactions on the contaminated surface

The main technological aspects of the production of building ceramics are given. Based on the analysis of literary sources, a comprehensive assessment of the feasibility of using construction ceramic waste as a secondary raw material for the production of new building materials was carried out. Based on the research of modern scientists, it has been established that the waste from the scrap of building ceramics is suitable for use as an aggregate, partial replacement of cement and a reactive additive in concretes and mortars. When using scrap of con-struction ceramics as an aggregate, it is recommended to limit the substitution of natural aggregate at the level of 20-30%, together using various additives: plasticizing and improving rheotechnological and physico-mechanical properties of concrete. Finely ground waste from brick scrap has pozzolan activity and, when used as a reactive additive or partial replacement of cement in concretes and mortars, up to 20-25% can improve the structure of cement stone, increase strength, reduce macroporosity and penetration of chloride ions, and increase sul-fate resistance. This kind of binder is prone to a later set of strength compared to Portland cement. In addition, the waste of building ceramics can be used in the production of alkali-activated cements and slag-alkali binders, as well as s raw materials for the production of new bricks or the construction of road surface bases. It has been revealed that the production of building materials and products based on con-struction ceramics waste is a promising direction for the development of construction production. It is possible not only to obtain materials of equal quality to products based on natural raw materials, but also with improved characteristics.

In the modern construction industry for increasing the thermal resistance of structures and reducing heat losses, casting foams based on reactive oligomers with high performance characteristics are widely used. At the same time, special attention is paid to the use of polyisocyanurate foams (PIR). However, in the scientific and technical literature there are practically no data on the influence of the composition of polyisocyanurate foams on their thermal properties. The purpose of this work is to determine the influence of isocyanate/polyol ratio, modifier content (trichloropropyl phosphate) and apparent density of foams on thermal properties of casting PIRs. The thermal properties of PIRs, when heated in the temperature range of 30-800 ⁰C in nitrogen atmosphere and in air, were investigated using a multimodal thermal analytical complex DuPont-9900 (heating rate 20°C/min). It is revealed that thermo-oxidative decomposition of polyisocyanurate foams is a pronounced, two-stage process, and the destruction of PIR in inert medium (nitrogen) is a one-stage process, which indicates different mechanisms of decomposition of foams in air and nitrogen. As a result of experimental studies, it was revealed that the investigated PIRs are more resistant to thermo-oxidative degradation than to thermal degradation. The thermal properties of the above foams depend on the isocyanate/polyol ratio and TCPP content. The density of polyisocyanurate foams insignificantly affects their thermal stability. At the optimal content of initial components PIRs have higher thermal resistance compared to rigid polyurethane foams (FPU).