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Introduction. Surface treatment plays an important role in protecting decorative stone and concrete from the effects of harmful environmental factors. To protect stone surfaces, dietary supplements in the form of carbonatogenic bacteria, the product of which is calcium carbonate, can be used.Materials and methods. The selection and analysis of publications containing the results of research and experiments, which allow to draw conclusions about the feasibility of using bacterial solutions for surface treatment, has been carried out.Conclusions. The formation of a layer of calcium carbonate on the surface of the material reduces gas permeability, reduces water absorption, increasing the durability of concrete. It was found that the surface treatment of cement stone with solutions containing cultures of urobacteria strengthens the surface layer of the stone, but does not restore its strength. It is important that the formed layer of calcium carbonate on the surface of the material does not clog its pores. The chemical and structural similarity between the processed material and the resulting carbonate compounds must be observed. The dosage of urea and calcium chloride should correspond to the number of bacterial cells, since excess components of the nutrient medium leads to their accumulation in the pores.

The advantages and disadvantages of ceramic bricks production by the method of semi-dry pressing, using traditional technology, are considered. Urgent problem of improving the available clay rocks’ properties, depleted in clay fractions and containing large amounts of dust particles is appeared in many regions due to the shortage of high-quality clay raw materials. The used materials were clay rocks of the Novosibirsk region. Research methods were introduction of directional additives to the composition of raw mixes that affected the compressive strength, water absorption, brightness and color of the burnt shard. The research results showed the need for an individual approach to the raw materials of each field. Types of additives, contributed to reducing water absorption, eliminating crack formation, increasing strength, expanding the color range of products, were identified.

Introduction. This article discusses the possibility of expanding the colour palette of a ceramic shard. Due to the shortage of high-quality clay raw materials for the manufacture of plastic molded facing bricks, the problem of manufacturing ceramic wall materials by semi-dry pressing from low-quality clay rocks is urgent.Materials and methods. The main raw material was non-caking clay raw material with a low content of clay and a high content of silt particles. Some corrective additives were used to expand the colour palette of ceramic bricks. In the article, the authors used both standard methods for determining the physical and mechanical properties and modern methods for studying the phase composition of materials.Results. The possibility of enriching the colour range of a ceramic shard based on non-sintered clay raw materials has been experimentally confirmed, provided that the mixture contains flux additives. When receiving products with a clarified shard, light-colored flutes should be used.Conclusion. The possibility of enriching the colour range of a ceramic cap by adding white-burning clay, introducing bleaching and chromophore additives and technogenic products has been established. Due to the differences in the chemical composition of clay raw materials from individual deposits, an individual approach to each of them is required.