Problem statement. One of the methods of improving the stiffness characteristics of FRP in construction practice is their external reinforcement with the use of carbon composites. The deformability of such systems is due to both the selection of components and the study of their creep. The purpose of this work is to study the deformability, temperature and time dependence of creep of fiberglass plastics externally reinforced with carbon fabrics on epoxy adhesives with different amounts of plasticizers. The objectives of the study are: investigation of deformation of fiberglass plastics externally reinforced with carbon fabrics on epoxy binder with different content of plasticizers in the area of elastic deformations at normal temperature, investigation of the creep of samples on four-point bending by the method of step isotherms. Results. We investigated the deformability, temperature-time dependence of creep of the system "pultrusion fiberglass - epoxy adhesive compositions with different amounts of plasticizers - carbon fabric". According to creep curves with the increase of plasticizers in the composition of epoxy resin, an increase in the deformability of the systems in the studied temperature intervals is observed. An approach to the experimental investigation of the temperature-time dependence of creep of systems using the method of step isotherms is proposed. Conclusions. The significance of the obtained results in the construction industry lies in the use of the method of step isotherms for the experimental study of the temperature-time dependence of the creep of fiberglass plastics externally reinforced with carbon plastics and is recommended in solving scientific and engineering problems.

Problem Statement. In recent years, modified bitumen has been widely used in road construction. One of the main requirements for the quality of bitumen binders is a stable adhesive ability to mineral materials of various nature and the stability of technological and operational properties over time. The modification of bitumen by elastomers of various composition and structure contributes to the increase of these indicators. The purpose of the study is a comparative assessment of the effect of oxidized petroleum road viscous synthetic thermoplastic elastomers of various chemical structures on the properties of bitumen. To achieve the goal, the following tasks were solved: 1. Study of the properties of road binders modified with individual polymers of the class of thermoplastics. 2. Determination of the effectiveness of the use of synthetic thermoplastic elastomers based on butadiene monomers as modifying agents for petroleum road bitumen. Results. The initial stage of the study was to assess the basic characteristics of the raw materials of the multicomponent system: oxidized petroleum bitumen and thermoplastic elastomeric materials of two types. Investigation of quantitative influence of modifying agents was carried out using butadiene styrene thermoplastic elastomer and syndiotactic 1,2 polybutadiene. During the experiment the dynamics of changes of bitumen properties indices has been revealed, modified separately by each thermoplastic elastomer in an amount from 0 to 5 wt. %. It has been shown that in order to reach the existing normative requirements for polymer-bitumen binders it is advisable to use linear butadiene styrene thermoplastic elastomer. For syndiotactic 1,2 polybutadiene an increased, in comparison with SBS-polymer, solubility in complex multicomponent oil products has been noted. This is an absolute advantage while creating highly saturated mortar compositions. Conclusions. The conducted studies demonstrate the effectiveness of the use of polymer materials such as thermoplastics to regulate the quality indicators of bitumen binders. The expediency of using modifying agents of different composition is evaluated. Due to the imminent introduction of the main provisions of the volumetric and functional design system, the data obtained can be used for the development of bitumen binders of different PG brands. Therefore, it is considered important to continue research in the field of mixed compositions based on thermoplastics of various chemical structures in order to optimize the compositions of road binders modified with polymers.

Problem statement. The component of external reinforcement systems that is most susceptible to the effects of operational factors is epoxy adhesive. The purpose of this work is to study the effect of changes in the elastic modulus of an epoxy adhesive on the creep of a reinforced structure. The objectives of the study are: the development of compositions of epoxy adhesives having regulated elastic modulus, conducting strength and creep tests. Results. The paper presents the results of stress-strain state studies of reinforced concrete beams reinforced with piles. According to the results of the study, it was revealed that a decrease in the elastic modulus of the adhesive leads to an increase in deformability and reduces the strength of reinforced beams. Conclusions. The significance of the results obtained for the construction industry consists in establishing the dependence of the stress-strain state on the physical and mechanical characteristics of adhesives used in strengthening building structures. These results can be used in the development of adhesives with specified characteristics for certain operating conditions.

Problem statement. As studies in the field of external reinforcement systems show, a change in the elastic modulus of adhesives used in reinforcement has an effect on the stressed-strained state of reinforced structures. The purpose of this work is to regulate and predict changes in the elastic modulus of epoxy adhesives. The objectives of the research are: the development of dispersed-filled epoxy compounds with various elasticity modules, conducting strength and creep tests and studying predictive models for predicting the modulus of elasticity of dispersed-filled epoxy polymers. Results. Epoxy compounds with different elastic modules have been developed and their physical and mechanical characteristics have been determined. The analysis of models for predicting the elastic modulus of epoxy polymers has been carried out, and good convergence of analytical models with experimental data has been revealed. Conclusions. The significance of the results obtained for the construction industry consists in identifying the operating range for predictive models depending on the content of the dispersed filler. This will allow you to pre-simulate the physical and mechanical properties of adhesives when developing them with predefined characteristics.

The analysis for the functioning of brick factories and stocks of high-quality high-grade raw materials showed their depletion. Therefore it is necessary to investigate and study such waste products if it is possible to use them as leaners and sintering intensifiers, thanks to which it will be possible to use substandard clay raw materials. Enterprises have adopted such experience, which they also used as a tool for protecting environmental systems. The purpose of the work: a) creation and implementation of compositions for the process of obtaining ceramic wall bricks based on hydrosluidic low-melting clay with an admixture of montmorillonite, which does not give a positive result when used as an independent raw material without the use of a leaner and sintering intensifier; b) to investigate the effect of metallurgical iron-containing slag obtained from copper smelting on the technical characteristics of ceramic bricks. Results. It was revealed that the dried brick made of hydrosluidic low-melting clay with an admixture of montmorillonite, without the use of a leaner, after drying does not meet the requirements of State Codes (GOST) in terms of the number of cracks without destruction, the number of through cracks and numerous cuts as a result of the high sensitivity of the charge to drying. Metallurgical slag introduced into the ceramic mass based on Kyshtyrli clay even in an amount of 10% reduces the number of cracks, increases strength (compression and bending) and frost resistance. The optimal composition for the production of ceramic bricks is a composition containing 15% slag. Conclusions. Studies have revealed that cracking in the production of bricks based on the Kyshtyrlinsky clay deposit without the use of leaners is observed in the following proportions: in tunnel dryers -51% (of the total number of cracks) and after firing (in furnaces) – 49%, approximately in equal parts. Metallurgical slag reduces the number of cracks, increases technical performance. The optimal composition for the production of ceramic bricks is a composition containing 15% slag, the grade of brick with such a content corresponds to M125 and excludes various types of defects on products. A further increase in the content of metallurgical slag does not reduce the grade of the brick, but at the same time various types of defects appear, for example, a black core.

Statement of the problem. The dynamic and sustainable development of the road construction sector requires innovative development and a transition to “green development” technologies, which involve reducing the impact on the environment and reducing the carbon footprint, as well as reforms in the production of environmentally friendly, cost-effective building materials and technologies for working with them. Cold recycling technology meets the challenges of our time. However, it is currently at its formative stage and requires activity in the field of research on the advantages and disadvantages of this or that type of asphalt granuloconcrete, its durability and collaboration with asphalt concrete. The purpose of the work is to study and comparatively analyze asphalt granuloconcrete types M and K from the standpoint of physical, mechanical and operational properties, as well as to evaluate their joint work with asphalt concrete in the design of road pavements. The objectives of the work are to study the influence of mineral and complex binders on the physical, mechanical and operational characteristics of granular asphalt concrete; to assess the impact of the methodology for selecting and testing composites; to analyze the effectiveness of joint work of asphalt granuloconcrete types M and K with asphalt concrete. Results. The paper presents the results of studies of asphalt granulocrete types M and K selected and tested using two different methods. The obtained data demonstrated that asphalt granulocrete of type K is closest to asphalt concrete in terms of properties. When cement is used as a part of asphalt granulocrete, a decrease in its strength characteristics is observed when bending at a temperature of 0 ° C relative to asphalt concrete. Thus, the bending strength decreased by more than 20%, and the deformation by more than 40%; the compressive strength at a temperature of +200C after 10 freeze-thaw cycles and the frost resistance coefficient decreased by 2 and 3 times respectively. The analysis of the laboratory model of the pavement structure consisting of "AGB type K + asphalt concrete" demonstrated that its bending strength at a temperature of +20 0C and deformation exceed the indicators of a similar model from "AGB type M + asphalt concrete" by 13% and 185% respectively. Conclusions. The significance of the results obtained for the construction industry lies in the fact that the features of the joint work of asphalt granuloconcrete layers with asphalt concrete have been identified. The best joint work is characterized by prefabricated structures made of asphalt granuloconcrete type K and asphalt concrete due to the similarity of strength and deformation characteristics in a wide temperature range. To ensure water and frost resistance, compositions of type M asphalt granular concrete require adjustment with special additives.

Primary studies have shown that in the joints of wooden structures on threaded washers premature destruction of the adhesive seam occurs and the washers detach from the wooden element, due to the action of forces directed from the plane of the washers. It is proposed to compensate for these forces by additional compression of the junction node with overlays that are tightly adjacent to the connected elements of the node. The purpose of the research is to study the work of connecting wooden structures on glued threaded washers when compressing a node with steel linings. The objectives of the study are to conduct an experimental study of a series of samples to determine destructive loads and extreme deformations, to investigate the nature of the destruction of joint samples, to determine the feasibility of using this type of joint in wooden structures. Results. In order to study the nature of the work of the joint in question, experimental studies of a series of samples were carried out. Destructive loads are determined, deformation graphs are constructed. The factors influencing the destructive load and the mechanism of destruction of samples are investigated, the analysis of the effectiveness of the use of alternative methods of perception of the expansion of washers in the junction node is carried out. Conclusions. Tests have shown the general inefficiency of compression of the junction with steel plates. Since other ways of perceiving the spacer in washers will lead to a significant increase in the complexity of manufacturing and assembling the joint, it is concluded that the use of glued threaded washers in joints of wooden structures is ineffective. The analysis of the research results revealed the possibility of using screw-on threaded washers without the use of an adhesive composition, which will significantly reduce the manufacturing time of the structure.

Problem statement. Well-known variants of cross-sections of composite beams, which are presented in manuals, articles, patents of researchers, they have their advantages and disadvantages. Composite (steel-concrete) beams with partial embedding in a concrete slab have been studied little, that’s why there is a need for a preliminary assessment of the bearing capacity of the section, which can be performed by numerical methods. The purpose of the work is to study a little-studied variant of a composite (steel-concrete) beam. In the connection with the purpose above the following tasks have been solved: to describe the advantages of a composite (steel-concrete) beam with partial embedding of a steel I-beam into a concrete slab and to analyze the stress-strain state according to normal sections. Results. The paper presents the advantages of the proposed variant of a composite (steel-concrete) beam. A model describing the stress-strain state of a composite (steel-concrete) beam in normal sections is presented. Conclusions. The significance of the results obtained for the construction industry lies in the fact that the proposed version of a composite (steel-concrete) beam with partial embedding of a steel I-beam into a concrete slab will increase the bearing capacity of floors, reduce the cost of construction and installation work and material costs.

Problem statement. The relevance of this study is due to the need to implement effective projects in the agro-industrial complex, which is one of the key factors in ensuring food security. This aspect represents one of the priority directions of the state policy during the long-term period. The purpose of the study is to review the design experience and prospects for the development of construction of industrial poultry farms. The objectives of the study are to review the experience of design and survey works within the framework of the project «2nd order broiler reproducer»; to develop an effective, technological and environmentally sustainable complex for industrial poultry farming, including the use of modern building structures, materials, engineering systems and facilities; to propose the basis for the development of methodological recommendations for the creation of design documentation of industrial facilities in the field of poultry farming. Results. The main result of this study is an integrated approach to project development aimed at creating the efficient, technological and environmentally sustainable complex for industrial poultry farming. This approach includes the use of modern building structures, materials, engineering systems and facilities, as well as consideration of all regulatory requirements and standards. Conclusions. The significance of the results obtained for the construction industry is manifested in the integrated approach to the design of industrial poultry facilities proposed by the authors of the study.

Problem statement. The metro tunnels construction in conditions of cramped urban development is a technogenic risk source for existing and newly designed buildings and structures. In turn, the construction of new buildings may negatively affect the operating conditions of metro structures. In this regard, when designing buildings and structures in the area of metro lines, it is necessary to carry out a comprehensive assessment of their mutual influence. The purpose of the work is a geotechnical forecast of the influence of the metro on the designed building in Kazan and the influence of the building on the metro. The objectives of the study are the selection of the most optimal design of the foundation and soil base, which allows reducing the level of vibrations on the surface of the foundation from the influence of the movement of metro trains to the permissible limit, and calculation of the base of the foundation of the designed building based on deformations, taking into account the vibration impact from the movement of metro trains. Results. The design solution for the base and foundation of the designed building, selected by calculations, providing for the installation of a slab foundation on a compacted layer of crushed stone with a thickness of 1000 mm, makes it possible to reduce the level of vibrations from the movement of metro trains to the permissible limits provided for by sanitary standards SN 2.2.4-2.1.8.566-96. Conclusions. The significance of the results obtained for the construction industry is that the approaches to calculations recommended in this article and the results obtained for a specific structure can be used in the development of measures that reduce the negative mutual influence of newly designed buildings and the metro.

Problem statement. The need to increase the efficiency of quality control of raw mixtures and printed products, to eliminate identified deficiencies in order to obtain high-quality construction products is impossible without identifying the types of defects that arise, damage and inconsistencies of concrete in 3D concrete printing (3DCP), which determines the relevance of the problem being solved. The purpose of the research is to develop a classification of defects in concrete and mortars formed during 3DCP. The objectives of the research are to carry out quality control of 3D-printed samples from concrete and mortar mixtures using visual and measuring methods, identify defects, establish the causes of their occurrence, develop definitions and symbols of defects and concrete and mortars based on mineral binders in additive construction technology. Results. The classification of defects, definitions and symbols of defects in concrete and mortars based on mineral binders in 3DCP has been developed, taking into account their formation during the process of molding, hardening and operation. The results obtained are recommended for use in documentation of all types of scientific, technical, educational and reference literature in the field of additive construction manufacturing. Conclusions. The significance of the results obtained for the construction industry is to ensure the unity of terminology for defects in concrete and mortars that arise in 3DCP, the ability to quickly and objectively identify their defects during 3D printing and make decisions to eliminate them (if necessary), improving the quality of construction products.

According to expert assessments in the field of managing production structures when implementing technically complex projects, there is a lack of standardized methods for assessing the efficiency of production processes in this area. This is due to the lack of a methodology for selecting optimal production structures, as well as possible changes in the requirements of regulatory documents, a variety of technological approaches and factors for the occurrence of errors. As a result, there is an urgent need to develop a model designed to assess and ensure organizational and technological reliability in order to increase the efficiency of production structures during the construction of technically complex facilities. This article pays attention to the main factors influencing the efficiency of production structures and the organizational and technological reliability of decisions made, and also discusses their features. It is proposed to develop a system for assessing the level of efficiency of production structures, taking into account organizational and technological reliability and the specified factors. The purpose of this study is to create a system for assessing the level of efficiency of production structures, taking into account organizational and technological reliability. The paper presents the results of the research that made it possible to develop a model for assessing the efficiency of production structures during the construction of technically complex facilities. This model takes into account the multifactorial nature and characteristics of this area, which makes it an important tool for optimizing production processes. The significance of the results obtained lies in the fact that the developed model is an essential tool for assessing the efficiency of production processes in the industry under consideration. The use of this model will allow us to take into account a variety of factors and make informed decisions in order to optimize production structures.

Problem statement. A significant disadvantage of additive manufacturing for construction is the possibility of the formation of “cold” joint between layers at significant time intervals during the printing process, which leads to a significant decrease in the strength and durability of finished products. The goal of the research is to develop a technological solution to improve additive construction production by increasing the adhesion of layers during long breaks in the 3D concrete printing. The objectives are to study the influence of a multifunctional additive for the transition layer in 3D printing technology on the required duration of a technological break and to identify the dependence of the adhesion strength of layers of fine-grained concrete of the basic composition with the transition layer on the duration of hardening of the samples and the type of multifunctional complex additive. Results. It has been established that the installation of a transition layer from a modified concrete mixture with a slight decrease in the adhesion strength of the layers (1.5-9%) allows for long technological breaks in the range of 3-12 hours. A technological solution has been developed in additive construction production using the layer-by-layer extrusion method, based on the device transition layer of fine-grained concrete mixtures modified with multifunctional complex additives, laid before a technological break, which allows you to specifically regulate its duration in a wide time interval (3-12 hours) while ensuring high quality of finished construction products. Conclusions. The significance of the results obtained for the construction industry lies in the improvement of additive manufacturing for construction, which makes it possible to carry out construction 3D concrete printing with technological breaks without compromising the quality of the resulting construction products.

The work of thin-walled metal structures of an open profile, common in construction practice, is characterized by a significant effect of section deplaning on the bearing capacity, which determines the relevance of research to determine the stress-strain state of sections during bending and constrained torsion, taking into account plastic deformations. The purpose of the study was to develop a numerical mathematical model based on the method of variable elasticity parameters, which allows sufficiently accurate determination of the normal stresses of the cross sections of rod metal structures, taking into account plastic deformations under constrained torsion and cyclic loading. The objectives of the research are: development of a numerical mathematical model based on the method of variable elasticity parameters; implementation of a mathematical model in the form of a program; verification of the developed program. The article presents a mathematical model that allows us to determine the normal stresses in rod metal structures under constrained torsion, taking into account the development of plastic deformations. The model is implemented as a program in the Python programming language and verified in the elastic and plastic stages of working with analytical and numerical (finite element method) solutions. Deviations of the maximum stresses in the cross section according to the method of variable elasticity parameters from analytical and numerical solutions in the elastic stage amounted to no more than 5%, which indicates the applicability of the method under consideration to solving problems of the combined action of bending moment and bimoment forces in the elastic stage of work. The stress distribution over the cross section during plastic deformations and subsequent unloading using the method of variable elasticity parameters is sufficiently consistent with the results of the finite element method, which indicates the applicability of the proposed model to solve problems in the elastoplastic stage under cyclic loading. The results obtained can be used to refine calculations in the design of metal structures experiencing the combined action of bending moment and torsion.

The main areas of gas fuel use (industry, energy engineering, domestic purposes, heating) have their own characteristics. Different categories of consumers require reasonable volumes of gas at a given pressure; gas consumption is uneven across territories and depends on the number and variety of consumers. Planning of the structure of the gas supply system is carried out on the principles of reliability, environmental safety, social significance and economic efficiency. The work is devoted to improving the reliability of the gas supply system during the period of long-term planning for residential and public areas of standard functional development. The goal of the work is to improve the technology of natural gas distribution based on the development of the optimal structure of the gas supply system. The objective of the study is to identify the relationships between the structure of gas distribution networks of territories and the planning zoning of the territory, natural and climatic factors and volumes of gas consumption. The most significant result is the methodological substantiation of the criterion for making long-term decisions on the structure of the gas supply system. Based on technical and economic indicators, a tendency has been identified to increase the material characteristics of the gas supply system depending on the building density. The calculation of the gas supply system is carried out taking into account the load for heat supply on the basis of the model of uniformly distributed gas flow across the site. This calculation model makes it possible to ensure the economic efficiency of gas supply projects under the conditions of phased commissioning of network sections. The novelty of the results lies in the improvement of the method for planning the development of the gas supply system in conditions of differentiated population density. The possibility of efficiency of investments in the development of infrastructure of territories increases depending on the density of development

Problem statement. The development and increase in the capacity of industry, including enterprises of the fuel and energy complex, leads to a significant increase in the consumption of fresh water. Using the example of thermal power plants, an increase in production capacity entails the increase in the need for desalinated water, which is used as a working fluid, which means that the productivity of water treatment plants increases. Any production is associated with water consumption, which leads to depletion of resources and a significant reduction in the number of sources of water suitable for household and drinking needs. In addition, enterprises discharge waste water into reservoirs, which leads to pollution of aquaculture. Considering that water purification technologies for household and drinking purposes were developed in the middle of the last century, today these installations are obsolete. Increasingly, consumers complain about the inconsistency of the quality of household drinking water with the standards for organoleptic indicators (smell, taste, aftertaste). Therefore, the purpose of this work is to analyze the water quality of household and drinking water supply by sample parameters in the context of the districts of the city of Kazan by season in the period of 2021-2022. To achieve this goal, the following tasks were set: studying the water supply systems of Kazan; conducting laboratory studies in certain districts of the city in the period of 2021-2022 and analyzing average indicators of drinking water quality. The following methods were used for the analysis: titrimetric, turbidimetric and potentiometric. Based on the results obtained, measures were proposed to improve the quality of water for household and drinking purposes. Results. Laboratory studies were aimed at determining the following indicators: total salinity, electrical conductivity, hydrogen index, total hardness, permanganate oxidability, alkalinity, content of chlorides, ammonium ions, total iron (III), sulfate ions. The choice of determining exactly these indicators was made considering consumer complaints and their possible causes, as well as the instrument base of the university laboratory. Indicators such as total salinity, specific electrical conductivity, alkalinity, hardness, and sulfate ion content characterize the qualitative and quantitative composition of deposits on the inner surface of pipelines. The hydrogen index, total iron (III), and chloride content are characterized for corrosion aggressiveness (drinking water may have an unpleasant odor and taste, as well as have an increased color). Permanganate oxidizability and the content of ammonium ions were determined in order to determine organic compounds and the cause of their appearance. Excess of ammonium ions indicate the presence of ingress of sewage. During the experiments, it was found out that some indicators are at the boundary conditions of the maximum permissible concentrations, which can negatively affect the livelihoods of the population using this water. To solve this problem, recommendations were given to reduce the negative factor. Conclusions. Based on the results obtained, measures were proposed for the water supply industry, which consisted in the implementation of programs for the modernization, construction and reconstruction of centralized water supply facilities to improve the reliability of operation, ensure a favorable environmental and epidemiological situation, reduce the cost of operation and repair of the complex, connect the suburbs of Kazan to centralized water supply and sanitation, as well as creating a reserve capacity and replaced worn-out networks with an increase in diameter to increase the system capacity.

Psychiatric clinic in Kazan due to the specifics of the medical purpose had certain architectural and planning features. They reflected the level of achievements in the design and construction of buildings of medical institutions of this kind at the beginning of XX century in Kazan and the Kazan province as a whole. The relevance of the study is caused by the insufficient study of this cultural heritage site. The subject of the study is the features of the spatial planning structure and style of the building. The research methodology includes the study of archival documents, bibliographic materials and full-scale surveys of the building, conducting a comprehensive analysis of the site with special types of research (comparative, compositional, stylistic, etc. types of analyses). The aim of the work is to study the features of the architecture of psychiatric university clinics using the example of the building of the Psychiatric Clinic in Kazan. To achieve the purpose of the study, the following research tasks were solved: 1. to conduct bibliographic and archival research on the topic of the study. 2. to analyze the architecture of the Psychiatric Clinic in Kazan based on the revealed data from bibliographic sources, archival documents and materials of the full-scale survey of the building conducted by the authors. 3. to compare the results obtained with data on the architecture of similar clinics in other regions of Russia and identify the features of the spatial planning structure and style of the building. The work performed made it possible, as the results of the study, to identify the features of the spatial planning solution and the style of the building and correlate them with solutions of this type of buildings in other cities of Russia at the beginning of XX century. The conclusions of the study allow us to establish general architectural and planning principles of the organization of such specific buildings as psychiatric clinics in Russia at the beginning of XX century.

Problem statement. Studying the work of prominent Kazan architects of the Soviet period helps to understand the all-Russian and regional processes of formation of Soviet architecture. The post-war period of the formation of the Kazan architectural school remains poorly studied. In a broad sense, the relevance of this study is related to the need to create a professional regional scientific base for the formation of modern architecture of the Republic of Tatarstan, which has features of cultural identity. The purpose of the study is to systematize competitive projects and determine the design methodology of prominent Soviet architects of Kazan in the post-war period. The research objectives are to identify and introduce archival sources on the research topic into scientific circulation; to study bibliographic sources on the use of national and regional traditions in the Soviet era; to analyze the design methodology of Kazan architects in the context of national and regional traditions. Result. As a result of the conducted research, archival materials submitted to the competition of collective farm clubs, managing boards, residential buildings and small architectural forms by prominent Kazan architects A.G. Bikchentaev, N.P. Kozlov, M.K. Iglamov, D.M. Fedorov, P.A. Sanachin and others were identified, systematized and introduced into scientific circulation. The professional tasks of the post-war period are defined, the design methodology is analyzed. Conclusions. The creative method of the Soviet architects of Kazan in the post-war period was based on the unique synthesis of regional heritage and techniques of the existing classical architectural and artistic style. The pleiad of prominent architects of Kazan formed the foundations of scientific research of regional traditions and derived techniques for their use in the architecture of mass post-war construction in the territory of the Republic of Tatarstan. The architects of Kazan developed a unique ornamental system of their time, which is the heritage of the architectural culture of Tatarstan.

The Park named after Petrov is one of the oldest parks in the city of Kazan, located on the border of the former Porokhovaya Sloboda district. Despite its high memorial and historical value, today the territory is in need of development. On the territory of Petrov Park it is necessary to create a comfortable and functional tourist and recreational environment for comfortable use. Guests and residents of the city will be able to get closer to the history of the outstanding enterprise, cultivate in themselves and their children a feeling of pride and patriotism. The purpose of the study is to develop tourist and recreational environment on the territory of Petrov Park in Kazan for its inclusion into the existing tourist environment of the city, creating a comfortable favorable environment for guests and residents of the city. Results. Based on the existing condition and recreational potential of the territory, field studies performed, identified principles for the reconstruction of memorial parks, analysis of sources and iconography, a concept for improving and increasing the tourist attractiveness of the recreational environment on the territory of the Petrov park of Kazan was developed. In accordance with the study, a master plan of the territory was developed, as well as views. Conclusions.1. The territory of Petrov Park has significant potential for development. 2. Based on the analysis of domestic and foreign experience in the design of memorial parks, the principles of reconstruction of memorial parks have been identified. Memorial parks should play an educational role, tell the history of the place through their content, and also meet the requirements of modern use. 3. The developed concept of improvement includes memorial objects, meets the identified principles of reconstruction of memorial parks, and also meets the standards of modern use. Thanks to the formation of a tourist route, including the memorial park and nearby historical sites, Petrov Park will be included in the city’s tourist system

Problem statement. One of the current trends in increasing the efficiency of roads construction is the use of soil-cement in the structural layers of road pavements. However, the widespread use of soil-cement in road-climatic zones with seasonal changes, daily temperature changes and transition through 0° C is hampered by the need to achieve a high level of physical, mechanical and operational characteristics of soil-cement layers of road pavements. In the technology of soil strengthening, increasing the level of these indicators is possible by adding a technological stage for modifying soil-cement, including water repellents based on organosilicon compounds with bulky aliphatic radicals. The analysis of the sources made it possible to establish that systematic studies on the influence of the structure and volume of the aliphatic radical of organosilicon compounds on the efficiency of modification of road soil-cement have not been carried out. To ensure the possibility of designing road pavements with layers of modified soil-cement, it is also necessary to establish the dependencies of the influence of hydrophobization on the design characteristics of structural layers, the optimal values of which will allow them to be used in structural calculations. Results. Based on the identified dependencies of the influence of organosilicon compounds with aliphatic radicals of high molecular weight, which contribute to an increase in the levels of physical-mechanical and design characteristics of soil-cement, three design options for road pavements of the IV technical category of the lightweight type with layers of modified reinforced soils were designed and calculated. It has been established that hydrophobization of soil-cement with iso-butyl-, octyl- and dodecyltriethoxysilane provides an increase in compressive strength in the range from 34% to 83 %, tensile strength in bending from 33% to 131%, freeze-thaw resistance coefficient from 35% to 76% compared with unmodified compounds. It has been established that modification of soil-cement with the studied organosilicon compounds helps to increase the level of design characteristics of soil-cement layers of road pavements and, in particular, hydrophobization of reinforced soil with dodecyltriethoxysilane provides an increase in the elastic modulus: at 6 % Portland cement by 64 %; at 10 % – 53 %; at 14 % – 44 %. Conclusions: The possibility of designing road pavement structures with layers of soil-cement modified with organosilicon compounds with bulky aliphatic radicals is shown. This will improve the efficiency of road construction. The obtained results of design and calculations of road pavement options will contribute to expanding the regional raw material base and extending the service life of highways when using soil-cement modified with organosilicon compounds