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This article describes the method of obtaining magnesium oxychloride cement for construction purposes. The study describes the possibility of introducing additives that intensify the process of burning magnesium-containing raw materials in the form of an aqueous solution to obtain a sludge of low humidity. The advantages of this method are described in comparison with the known method of wet granulation of ground raw material with an aqueous solution of the additive. A two-factor experiment was carried out to identify the optimal grain size of the raw material. The dependences of the change in the strength characteristics of a magnesium stone on the amount of the intensifier additive and the fractional composition of the modified raw material are described. The optimal area of the applied fraction and the amount of the additive, allowing one to obtain a magnesium stone with maximum compressive strength, has been established. The authors investigate the tendency of all samples to the formation of cracks. The reasons for the use of grain size outside the established range negatively affecting the quality of the magnesium oxychloride cement obtained are suggested.

The article provides a review of contemporary solutions targeted at protection of bearing structures from the fire in order to provide their standard fire-resisting conditions. Definitions of fire resistance and thermal conductivity of structures are given; the main factors determining the fire safety of buildings and structures are identified; the necessity of using the fire-retardant systems in construction is substantiated, and the most popular methods of such systems' arrangement are considered. The main groups of materials aimed at protection against high temperature and which impede distribution of open fire are described. The main principles when selecting fire-retardantmaterials are described. General practical advantages and disadvantages of fire-retardant materials are listed.

This article deals with the research dedicated to the formulation and testing algorithm of water amount adjustment tempering while producing concrete mixtures depending on raw material characteristics. The algorithm is intended for an automated quality control system of concrete mixtures of raw components, providing continuous data collection in real time. The article provides the necessity of automatic quality control implementation and adjusting the calculated compositions of concrete mixtures based on them. There is the discussion of factors discouraging the formulation and implementation of the given systems at the existing production of reinforced concrete products. There were formulated the ways of solving the problems, the scientific significance of the proposed projects was proved. There was revealed the main parameter of the concrete mixture, which provides the concrete quality obtained on its basis and factors influencing it associated with the physicochemical characteristics of raw materials are shown.