The applying of local building materials is an effective contribution to the savings of mineral resources, which are used for the production of basic building materials. Clay and gypsum compositions are the local raw materials in many regions of the country and some neighboring countries. The article discusses the method for determining the clay fraction in the clay and gypsum composition, as well as the method for assessing the rheological characteristics of the plaster mixtures for interior work based on clay and gypsum binder. It was established that the content of the clay fraction in the studied clay and gypsum composition is in the range of 30–32%. Plaster mixtures based on clay and gypsum binder can be considered as optimal compositions under the following conditions. The grade of mobility is not less than PK3 (8–12 cm) in cone penetration test, the ultimate shear stresses in the first seconds of the thixotropic hardening ensure no runoff for the adjusted thickness of the applied layer. With the mentioned mobility, the “creeping” on the concrete surface is 10% and less, and the “creeping” on the brick surface is no more than 5%. The allowable water-solid ratio is 0,46–0,50.

The article analyzes the property requirements of small-piece products used in road construction, specially those related to water and frost resistance. It describes the main features of the vibration technologies involved in the manufacture of building materials, in particular, paving slabs. The article presents conclusive results, obtained through scientific research, which allow us to establish the influence of both, the costs of the main components and the parameters of vibration compression, on the properties of the final product. Combining the analysis of classical methods with the results of experimental research, a methodology has been developed for reaching an optimal composition of fine-grained vibropressed concrete modified with active additives. It is shown that the particular strength achieved from the combination of vibroformed fine-grained concrete, whose average density is 2270–2320 kg/m3, with polymer multifunctional modifiers, is mainly due to the use of Portland cement, a modifying additive, and the pressure conditions employed during the experiment..

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Heat-insulating and structural-heat-insulating light concretes used in external enclosing structures significantly reduce the heat loss of a building in the cold season. The paper solves the problem of establishing criteria for evaluating the external walls made of light concrete blocks resistance to alternate freezing and thawing in laboratory conditions. A method for studying the frost resistance of masonry made of polystyrene concrete and cellular concrete of autoclave hardening during cycles of unilateral humidification-freezing-warming of wall fragments is proposed, which is closest to the actual operating conditions. Physical, mechanical and thermophysical characteristics of heat-insulating and structural concrete are obtained. The dependences of heat-protective qualities on the degree of moisture content of the material, as well as the strength of the thawing conditions of samples in water and air conditions are established. As the normalized parameters for assessing the frost resistance of light concrete masonry by unilateral freezing it is proposed to use the adhesion strength of blocks with plaster mortar, the strength of chemical anchors (breaking methods), as well as the passage speed of an ultrasonic impulse through the masonry thickness (non-breaking method). Based on the research results, recommendations for their implementation in regulatory documents are formulated.

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