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Introduction. To create concrete with a set of physical and mechanical characteristics, a rational selection of the components of the concrete mix is required, including the use of finely dispersed fillers, including those based on recyclable materials, and a highly effective chemical additive of a certain nature and reactive action, which has a complex effect on concrete system. Methods and materials. The effectiveness of the components in used additive was assessed by changing the indicators of compressive strength, tensile strength in bending, the assessment of which was carried out according to GOST 10180-2012 "Concrete. Methods for determining the strength of control samples. For carrying out scientific and experimental studies, the following materials were used: Portland cement CEM I 42.5N; natural sand; fine microsilica; complex chemical additive with increased plasticizing and reactive effects. Results. The combination of polycarboxylate polymers and nanodispersions of silicon hydroxide enhances the effectiveness of each component, which is reflected in a significant increase in the coefficient of crack resistance of concrete at high compressive strength. It has been established that when using a complex nanopolymer chemical additive, the increase in tensile strength in bending is 67% and it exceeds the increase in compressive strength by more than 30%. Discussion. An increase in hydration activity in the presence of a nanopolymer additive has a positive effect on the compaction of the emerging concrete structure. Confirmation of the formation of a dense and strong structure during the hardening of nanomodified concrete is an increase in the water resistance of concrete by 2.5 times and its frost resistance by more than 2.5 times. Conclusion. The advantage of nanomodified concrete is its increased chemical resistance to carbon dioxide and magnesia corrosion and, in accordance with the index of chemical resistance coefficient, CCSт> 0.8, and GOST R 58895-2020, the developed nanomodified concrete belongs to chemically highly resistant concretes. It is advisable to recommend nanopolymer concrete with high physical and mechanical properties for the manufacture of structures for overhead power transmission lines (OPL).

Introduction. The elaboration of foamed eco-friendly gypsum nanocomposites with low specific gravity, high thermal insulation, operational and technical and economic characteristics remains an urgent task. Controlled hardening of gypsum foam nanoassemblers using dry foaming agents is a promising direction in the technology of production of heat-insulating building materials. Methods and materials. The production of a foam gypsum composition was carried out in an ejector-turbulent mixer by mixing a gypsum nanobinder with functional foaming nanoadditives. Building gypsum G5 BII was used as a binder in the work; porization of gypsum compositions was carried out using an adsorbed foaming agent PBNS. Results. The transformation of liquid-phase foaming agents into solid-phase ones by binding water allows the production of gypsum foam compositions from dry mixtures, which gives high dosing accuracy, a good degree of homogenization of components and stable characteristics of foamed gypsum nanocompositions. In production conditions, a one-storey small-sized pavilion was built using a pilot 3D printer AMT S1160, in which vertical enclosing structures are filled with foamed heat-insulating nanostructured foam gypsum. Monolithic foam gypsum nanomaterial with a density of 300-400 kg/m 3 was used for insulation and sound insulation of attic floors during the overhaul of the historic building of the Veterans Hospital in Ufa. Discussion. The elaboration of technology for obtaining foam gypsum from dry mixtures is based on the advantage of manufacturing and using thermal insulation nanocompositions, which allows for significant punctuality of dosing and stable characteristics of foam gypsum building materials. Surfactants have a significant effect on the kinetics of the structure formation of the foam gypsum nanocomposition and slow down the coalescence of air bubbles. Conclusions. Nanoporous foam gypsum concrete, obtained as a result of controlled hardening, with a density of 400 kg/m 3 has a thermal conductivity of 0.12 W/(m•ºС) and a compressive strength of 1.4 MPa. The compressive strength of foamed foam gypsum using a dry foaming agent on sorbents is 17% higher than the strength of a heat-insulating nanomaterial prepared using traditional technology.