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The economic development of the Arab states is characterized by such trends as industrialization and urbanization, population concentration in large cities, saving land, increasing the number of storeys of buildings. Population growth in developing countries is causing acute housing needs. One of the most promising modern building materials is concrete and re-inforced concrete. The main components of concrete, as it is known, are a binder (cement), large and small aggregates. The creation of comfortable conditions is provided by the optimization of the “man-material-environment” system. The theoretical basis for the development of materials science is knowledge about geological processes and the genesis of rocks. The evolution of the development of binders goes along the way of complicating their composition and structure. In the development of materials science there is the process of controlling the structure formation of binders using nanodispersed additives. Nanodispersed additive is produced by grinding in various grinding aggregates of the silica-containing component, the cement, the carbonate constituents, superplasticizers, air-entraining additives, etc. The result is a very complex system. After we introduce a nanodispersed modifier in cements in an amount of 3 to 12%, they absolutely change the processes of structure formation. Thus, it was found that when adding a superplasticizer and a nanodispersed modifier, the compressive strength increases to 47% and the bending strength increases to 27%. The nature of the influence of the nanodispersed modifier on the properties of binders is established. Maintaining a nanodispersed modifier in the composition of Portland cement allows optimizing the process of structure formation of the component of a nanodispersed modifier and has a multifunctional value.

the relevance of the paper is due to the search for alternative sources of raw materials for the construction industry, associated with the disposal of man-made waste. The novelty of the article is to identify the scien-tific laws of the influence of demolition waste on buildings and structures on the formation of the micro-structure of lightweight and heavyweight concrete. Concrete waste was prepared as both fillers of cement materials and fine aggregates, based on which concrete with high mechanical properties was created. The mix design was carried out from the point of view of geomimetics, in particular, taking into account the law of affinity of structures. The strength characteristics of concrete mixtures were investigated in accordance with EN 12390-3. In addition, the microstructural, morphological and thermal properties of the raw materials and concrete were determined during 28-day curing. For the first time, the dense microstructure of the com-posite was ensured, both with Portland cement products and with hydration, and, in part, with hydration products of previously unreacted clinker, whose minerals are present in concrete waste and are activated when they are crushed. The use of demolition waste of buildings and structures as a filler of cementing ma-terial when replacing Portland cement up to 20% allows to obtain better compressive strength of both heav-yweight and lightweight concrete.

The need for high quality of building products and structures determines the urgency of creating new ways to control the processes of forming the internal structure of modern composite building materials. This article discusses some aspects and problems on designing high-powder composites based on the law of similarity. The results showed that the determination of the compositions of these materisls and high adhesion property to each other and a low deformation characteristic. The results demonstrated that this less deformation characteristics is due to the similarity of the thermai expansion coefficients of the concrete components.