No 9 (2025)

In last years, manufacturers and builders have been paying increasing attention to the ceramic bricks frost resistance, especially front ones. In most cases, this is due to the bricks destruction in the masonry, when responsibility is placed on the brick, since it is in plain sight. This often leads to long-term disputes in search of a culprit, although there may be many reasons for the bricks destruction in the masonry. These are salt corrosion under certain conditions, violations of building norms and regulations during buildings construction, various temperature deformations, etc. Currently, the situation when bricks are tested according to the GOST 530–2012 requirements are frost-resistant, but destroyed in the masonry, has become quite common. Increasingly questions on changing the bricks frost resistance testing methods are being raised. However in order to effectively protect ceramic brick manufacturers from unreasonable claims, fundamental issues must be resolved. Firstly, among the brickmakers” there is uncertainty and constant substitution of concepts between the frost resistance of ceramics as a material and bricks as a product. In this regard GOST 530–2012 makes no distinction (Appendix B). Secondly, there are common uncertainties for wall products (rock products, concrete wall stones) when the products are operated under the same conditions, but the requirements and testing methods differ. Thirdly, taking into account the significantly increased requirements for frost resistance, the development of accelerated frost resistance testing methods is an urgent issue. Fourthly, the issue of the possibility and legality of bricks taken from the masonry testing remains unresolved. There are also other issues that need to be addressed. The authors have identified the existing uncertainties and contradictions on the above issues and propose solutions to them.

Ceramic brick production continues to evolve, regardless of the forming method be it stiff, semi-dry, plastic, or traditional hand-molded” techniques. In the Russian Federation, despite the presence of specialized research institutions such as VNIIstrom, UralNIIstromproekt, NIIkeram, and others, many advancements have come from abroad in the form of fully automated, high-precision technological lines. While these imported systems are efficient and advanced, they are also costly. Their adoption has led to improved brick quality but also significantly increased production costs, resulting in reduced output and the closure of unprofitable factories. Meanwhile, our international counterparts continue their systematic research into new ceramic production methods and equipment-particularly focusing on innovative semi-dry pressing technologies. This article offers a concise overview of the key technological advancements in semi-dry pressed ceramic brick production, many of which were developed by Soviet and Russian scientists.

Ceramic bricks have high strength, durability, aesthetic appeal and are one of the most sought-after building materials. Presently dark-colored cladding materials are becoming increasingly popular in the construction industry. Black color of the brick gives the architecture expressiveness: depth, graphic and brutality. It emphasizes the shapes sculptural plasticity, reveals the structures tectonics and creates strong visual contrasting accents. During the research black ceramic stones based on domestic raw materials were obtained with the tanning of color-enhancing components, and their physical and mechanical properties and visual characteristics were studied. It is found that mudstones, which are widespread in Russia, can be used as a promising raw material for the production of black clinker bricks. Based on this raw material with manganese oxide and a color enhancer addition it is possible to obtain a high-strength ceramic stone with specified physico-mechanical and aesthetic characteristics.

The achievements in the field of brick waste disposal, which can be used as aggregates for concrete are analyzed. The brick waste usage as an aggregate solves both the problem of waste disposal and significantly reduces the economic costs of concrete production, often improving its quality. The properties of various types of aggregates and their effect on the concrete properties are analyzed. It is established that the strength of cement concrete with brick chips as the aggregate is higher. However, the strength of such concrete decreases when wet due to the high water absorption capacity of the brick chips. In addition, the cement composition, size and percentage of the aggregates affect the strength and other properties of the resulting concrete. The brick chips have properties tipical for the source material, but differ in structure. The pores make the material lighter. Brick splinters made of porous bricks have higher thermal insulation properties than those made of dense ceramics. The review also presents the research results in the field of household and industrial waste usage, such as incinerator’s bottom ash, metallurgical slags, silica fume from a ferroalloy plant, as well as brick debris as an additive to concrete, which allows to develop a technique for modified concrete production.

Althouhg the usage of combination of cement and various types of man-made raw materials from fuel and energy plants waste has long history, the study of the nature and mechanisms of fly ash and binder interaction is still relevant. This is due to the constantly changing variability of the fly ash properties because of fluctuations in the technological factors of its formation. The present work is about the study of the heat release kinetics during cement hydration in presence of additives from a wide sample of man-made raw materials (three acidic and two alkaline fly ash), as well as the study of structure formation processes during various periods of hardening with use of scanning electron microscopy. This made it possible to differentiate the reactions which leads to the main phases composing the cement stone are formed in dependence of the fly ash particles composition and structure. As a result, theoretical and experimental data on the nature of the interaction of the fly ash various types with cement have been supplemented, reflecting key factors (the content of oxides of CaO, SiO₂, Al₂O₃, Fe₂O₃) that contribute to active structure formation, and secondary factors that leveling the process of gaining the binder brand strength (particles content other than spherical shape; the presence of carbonaceous impurities).

Bitumen-mineral mixtures are widely used in asphalt concrete, waterproofing materials, blind areas production and other technologies. In this article, it is proposed to use artificial granite as aggregat in the bitumen-mineral mixtures production: waste product from the porcelain stoneware production, formed as a result of firing a charge consisting of natural raw materials – high-quality clay or kaolin, feldspar and quartz sand. This ensures stability of the chemical-mineralogical and physico-technical properties of the porcelain stoneware production waste, which peculiarity associated with low porosity. The need for the adhesive additives introduction has been identified. The cationic-type additives represented by cyclic imidazolines, which contribute to hydrogen bonds formation between the low-porous glass crystal structure of the porcelain stoneware production waste and organic binder is recognized as the most effective adhesive additive. It is shown that the physical and mechanical properties of the bitumen-mineral mixture based on the porcelain stoneware production waste is not worse then mixtures using natural mineral raw materials.