Currently, a large amount of research is devoted to the use of polymer composite materials applied for increasing the strength and durability of reinforced concrete elements. In compressed reinforced concrete columns, the bearing capacity depends on the eccentricity of the external force application and the corresponding stress-strain state, as well as on the arrangement and quantity of composite materials bonded to the surface of the structure. The choice of the arrangement scheme of composite materials depending on the stress state of the structure is of current interest for researchers. At the same time, studies conducted on centrally compressed elements often have contradictory effects. The main purpose of this study is to perform numerical experiment of a digital model for the centrally compressed concrete column reinforced with composite materials. The calculation results for 3 short columns with different reinforcement schemes are presented. It is shown that the use of composite materials to reinforce structures increases the bearing capacity up to 10%. Based on the study results, recommendations on the optimal schemes of reinforcement with composite clamps of inflexible columns reinforced in the transverse direction are proposed.

Keywords: reinforced concrete columns, normal sections, finite element modeling, reinforcement with composite materials

The organization of an enclosed space to ensure the basic processes of life (amateur professional activities, family communication, parenting, housekeeping, physiological and psychological recreation, maintaining health and hygiene) is traditionally an urgent task of architectural creativity. One of the possible solutions is the format of a low-rise (one or two floors) individual residential building, which includes several rooms (rooms) for residential and non-residential purposes, providing the necessary conditions for life processes. Low-rise individual residential buildings (with adjacent territories) are characterized by a number of advantages: a high level of living comfort, direct connection with the natural environment, the opportunity for full-fledged and versatile work and leisure, taking into account individual characteristics and preferences.

Keywords: individual residential building, composition, functional zoning, spatial relationships, living environment, efficiency, functional scheme, space, aesthetics, traditions, innovations

Research of modeling methods of steel structures's joints with the use of computer-aided engineering (CAE) systems is important, because scheme that most accurately reflects an actual state of the elements makes it possible to select their rational design. The aim of the article is to analyze an influence of modeling variations of truss joints on the stress state of a transverse frame. The object of the research is the plane frame of a two-story building with the truss made of hot-rolled steel equal leg angles. The subject of the study is the stressed state of the structure. In the article the following problems are solved: two models of the frame (with flexible and rigid truss joints) were created with the use of LIRA-SAPR CAE program, loads were calculated, results were obtained, the values ​​of bending moments and shear forces in the elements were analyzed. Conclusions were drawn about the influence of variant modeling of truss joints on the stress state of construction.

Keywords: CAE, flexible joint, joint, plane frame, rigid knot, static scheme, steel, steel angle, stress-strain state, truss

The article presents the results of the calculation of a high-rise building, the load-bearing frame of which uses wooden structures. With a significant height of the structure, wind load begins to have a significant impact on the deformability of the frame. A calculation scheme is proposed, in which two options for applying wind pressure are considered - on columns and in floor beams.

Keywords: high-rise building, permanent loads, short-term loads, instantaneous loads, modulus of elasticity, stiffness, stress, displacement, CAD

The work reflects the results of the influence of various factors on the deflections of the profiled flooring at the stage of concreting the slab. The relationship between the deflections of corrugated sheets in parts of its span and in parts of the total thickness of the slab at different heights of the design section of the slab has been established. The purpose of the work was to study the influence of various factors (the thickness of the corrugated sheet, the profile and height of the corrugations, the span of the slab) on the deflections of the profiled decking at the stage of concreting the slab, taking into account the recommendations of the standards. The work also studied the influence of the acquired deflection on the final deflections during the operation stage. The object of the study was a floor slab on profiled flooring. A calculation and analytical research method was used based on current regulatory documents. Research results. An assessment is made of the influence of corrugated sheet deflections on the applicability of various corrugated sheet spans in the range of spans from 3 to 6 m. Recommendations are proposed for limiting the maximum deflections of corrugated sheets at the stage of concreting the slab to 1/100 of the design span of corrugated sheets with a slab section height of more than 200 mm. Recommendations are given to limit the use of small thicknesses of corrugated sheets from 0.7 to 1.0 mm for spans over 3 m. Conclusions. Based on the results of the study, recommendations were developed for the use of optimal thicknesses of floor slabs on profiled flooring for various spans. Recommendations are given for limiting the thickness of the corrugated sheet depending on the span and the overall height of the slab section. The research results can be used in the design of steel-reinforced concrete floor slabs and in practical work when examining the technical condition of structures.

Keywords: concreting stage, corrugated sheet, deflection, profiled flooring, steel-reinforced concrete slab

Changes in the elastic characteristics of the soil for a base model that is inhomogeneous in depth are considered. The dependences of the modulus of elasticity of the soil and the coefficient of lateral pressure on the relative depth are obtained.

Keywords: modulus of elasticity, lateral pressure coefficient, pressure, compression curve

Engineering preparation of the territory for the construction and development of a residential complex is a difficult task. In the development area, fluctuations in the groundwater level are possible due to natural processes - flooding of the territory or during operation due to man-made processes. The work presents the results of the survey and assesses the impact of future construction on the hydrological situation of the built-up areas. Materials from engineering-geological surveys of the composition of soils in the lake water area and the building area were studied in order to determine the possibility of using alluvial soil from the lake for engineering preparation of the territory.

Keywords: engineering and geological surveys, urban development, alluvial soil, engineering preparation of the territory

The article discusses the method of constructing a horizontal protective screen made of large-diameter steel pipes used for the construction of tunnel-type structures using a closed method. The factors influencing the choice of this method are analyzed - features of the construction site, economic and time indicators. As an example, a project for constructing a protective screen made of large-diameter pipes for the construction of a two-section transport tunnel under railway tracks is considered. Diagrams are provided that provide basic information about the construction project, its main parameters are considered: geometric shape and dimensions, location of structural elements with an indication of their sizes. The sequence of construction work is presented, consisting of six main stages, starting with the construction of auxiliary working pits and ending with the construction of the internal structures of the tunnel. Such construction of tunnels in dense urban areas requires taking into account and minimizing their impact on existing structures and transport routes in the construction area. The article presents the results of numerical calculations of stabilized movements of the soil mass, confirming the effectiveness of this method.

Keywords: horizontal protective screens, tunnel-type structures, large-diameter pipes, soil deformations

Reinforced concrete flat slabs continue to be one of the most popular floor systems due to the speed of construction and their inherent flexibility in the layout of the premises. However, flat, non-rigid floors are subject to brittle fracture at the junction of the slab and column, which can spread and lead to the progressive collapse of a larger segment of the structural system. The lack of shear strength in two directions may be due to design errors, insufficient strength of the material, or overload.

Keywords: reinforced concrete slab, punching, transverse reinforcement, fiberglass, carbon fiber

The main defects of railway structures are identified, the damage of defects is characterized by the degree of influence based on the quality indicators of building structures, a mathematical model for assessing risk and damage is created, expert surveys are conducted on the nature of the conditions for the probability of defects and bringing them to damage, an algorithm for implementing the results on the construction site is presented.

Keywords: risk assessment, probability conditions, concrete works, risk-oriented approach, risk identification

The article considers the problem of sediment formation, sludge and corrosion on the heat transfer surface during the operation of heat exchange equipment at housing and communal services facilities. A new method of non-selective mechanical cleaning using a water hammer is proposed. The description and principle of operation of this cleaning system at the central heating station of the Ogarev Moscow State University are given. To confirm the effectiveness of the proposed technical solution, the results of thermal and hydraulic tests are presented.

Keywords: deposits, sludge, corrosion, cleaning, heat exchanger, water hammer, heat transfer

As of today, in Vietnam, to ensure stability and improve the quality of asphalt concrete, the main focus is on the application of new technologies, materials, or the improvement of design methods. However, despite significant achievements in this area, the issue of automating the processes of asphalt concrete mixture production management remains insufficiently researched and implemented. Based on the experience accumulated in Russia, the authors propose developing a system of adaptive control for the asphalt concrete mixture recipe, which contributes to the stabilization and improvement of production quality. In the article, the authors present the structure of the control system and its algorithms, as well as describe the results of modeling and evaluating the effectiveness of this system. The study shows that the adaptive control system for the asphalt concrete mixture recipe, developed based on the experience from Russia, successfully demonstrates its effectiveness in the conditions of Vietnam.

Keywords: asphalt concrete, asphalt concrete mix, Marshall stability, control system, formulation, simulation model, modeling, MATLAB, management efficiency

As part of the work on the PhD thesis on the creation of new systems and calculation devices for the design of reinforced concrete tanks for the storage of liquefied natural gas, work was done to determine the properties of concrete mixtures used in the construction of tanks in Vietnam, namely in the Hanoi area. A feature of the materials used for the manufacture of concrete is the use of local rocks, which have distinctive properties, which affects the strength and deformation properties of concrete. The article presents the results of experimental studies of the properties of concretes made with Vietnamese materials. A relationship was established between the modulus of elasticity of concrete and its prismatic compressive strength. As part of the study, 16 formulas of concrete mixtures on different materials from Vietnam were compiled and studied. As a result of the conducted research, the dependence of the modulus of elasticity and the intended strength of concrete was revealed, which will later be used in the creation of calculation devices for the design of reinforced concrete structures.

Keywords: concrete, reinforced concrete, materials, structures, modulus of elasticity, prismatic strength of concrete, deformations

In the conditions of dense urban development, the lack of parking spaces becomes a serious problem that requires a comprehensive approach to solve. It is the construction of new multi-level car parks that makes it possible to increase the number of parking spaces in a limited space. The foundation plays a critical role in the construction of multi-level car parks, as it must ensure the stability and safety of the entire structure. There are many aspects to consider when designing and constructing the foundation that help ensure the reliability and durability of the multi-level car park, which is especially important to prevent potential problems and accidents in the future. The article discusses in detail the technology of laying a pile-based foundation for the construction of a multi-storey car park located in Moscow.

Keywords: multi-level car park, rostver foundation, geodetic control, reinforced concrete beams, excavation pit

The article presents a way to increase the load-bearing capacity of a reinforced concrete column due to metal clips from the corners with an increase in the load on it. To ensure the joint operation of the existing column and the metal cage, the corners are subjected to prestressing, which is achieved by compressing the corners with jacks.

Keywords: reinforced concrete column, column reinforcement, metal cage, prestressing of the cage

Concrete paving slabs for road construction are made from mixtures consisting of hydraulic binder, fine and coarse aggregates and water. The prepared mixture of a given humidity is subjected to vibration molding under the following technological conditions: process duration 5–10 seconds, vibration frequency 30–50 Hz and pressure 70–80 kg/cm2. Hardening of freshly molded samples is carried out in a heat and humidity treatment chamber. It has been established that it is possible to replace natural coarse aggregate with fractionated scrap concrete. The compressive strength of concrete with aggregate based on recycled crushed stone is 300 - 400 kg/cm2, water absorption 4.8 - 6.2%, frost resistance F2 200 - 300. The proposed technology allows solving both economic and environmental issues for regions with large amounts of concrete scrap at temporary industrial waste storage sites.

Keywords: concrete mixture, vibroforming, modifiers, filler, waste, concrete scrap, strength

The presence of a large number of undeveloped areas within the city - now inactive enterprises - creates a negative impact on the urban environment. Since these territories are depressed spaces, the design of new residential areas with characteristic high-rise buildings seems to be a logical path for the development of the city. However, uncontrolled urbanization and dense multi-storey buildings represent a fundamental change in the human environment. The consequences of this approach lead to a deterioration in the air exchange of areas and contributes to the formation of “heat islands” that affect air pollution. This contributes to the deterioration of the environmental and social situation and the emergence of a negative perception of the environment among the population. The worsening of this problem may cause a deterioration in the social climate in large cities. The article analyzes the impact of dense high-rise buildings on the environment located on the territory of non-operating enterprises. Methods for solving this problem are indicated. The results of field observations and studies of the interhouse space are presented, on the basis of which the role of convective flows of thermal origin in the air exchange of urban space is revealed. A comparative analysis of projects for the development of the territory of a former house-building plant with complexes for various functional purposes is presented.

Keywords: urban area, air exchange, convective flows, temperature conditions, standard buildings, renovation, leisure facilities, depressed spaces

The practical significance associated with the development of automated software systems for calculating joints of steel structures of buildings and structures is noted. Using the IDEA Statica software package as an example, the calculation and analysis of the operation of a steel unit connecting the lower chord of a truss to a column was carried out. The order and sequence of entering the initial data for calculating the connection is shown. The calculation results present in tabular and graphical forms the equivalent stresses and plastic deformations of the main elements, as well as the results of inspections of bolted and welded connections of these elements to each other. A comparative analysis of numerical and analytical calculations was performed. Conclusions are formulated based on the results presented in the article.

Keywords: calculation model, connections, steel structures, component finite element method, design, nonlinear analysis, work analysis, stress, plastic deformation, bolted connection, welded connection

The article considers ecological and landscape features on the example of modern realized objects of wine tourism in the South of Russia. Based on the analysis of a number of new winery facilities and publications on this issue, some features in the context of modern architecture and its enotourism component are identified. Conclusions are made about the conformity of these features to the global modern trends in the design of buildings, such as environmental friendliness and resource conservation, respect for the landscape. On the example of the considered objects the hypothesis that the techniques of architect's work with the environment in conjunction with the original architecture increase the tourist attractiveness of wine production in general is confirmed.

Keywords: architecture, winery, enotourism, agritourism, landscape, project, landscaping, volume and planning solutions

The cases of uneven compression of a concrete cylinder in the case of simple loading and comprehensive uneven compression of a spiral-reinforced concrete cylinder under disproportionate loading are considered. The dependences of longitudinal, transverse and volumetric deformations on longitudinal stress are obtained.

Keywords: longitudinal stress, circumferential stress, longitudinal deformation, circumferential deformation, spiral reinforced concrete strut, shear strain intensity, shear stress intensity

The main means of seismic protection for increasing the seismic resistance of buildings and structures are described. The main problems associated with the design of special seismic protection equipment are outlined. The basic requirements for the design and calculations of steel frame frames taking into account seismic impact in accordance with the current design standards in the Russian Federation are analyzed. There is an insufficient description of the requirements specified in the standards for performing calculations and design of structures and their connections. Recommendations and instructions are given for taking into account the requirements of the standards for the design of steel frame frames. Schematic diagrams of special units for coupling columns with crossbars, necessary for design in seismically hazardous areas, are presented. Conclusions are formulated.

Keywords: special units, columns, beams, seismic impact, seismic protection, steel frames, plastic hinges, excess strength factor, forces, plastic moment, design.

This article presents a new developed calculation methodology, which includes provisions for standard calculations and takes into account the peculiarities of the operation of eccentrically compressed reinforced concrete structures operating at large eccentricities of load application. Adjustments have been made to the calculation methodology to take into account the following factors: the standard methodology uses the maximum tensile strength of reinforcement; proposals have been developed to determine the actual resistance of tensile reinforcement, which, in fact, will be significantly lower than the limit. Proposals are given that take into account the limiting deformations of concrete, which, in turn, will be a key quantity for determining the resistance of tensile reinforcement in the cross section. The article also presents the results of experimental studies of a flexible reinforced concrete pillar operating with a load eccentricity equal to e0 = 0.32h. Theoretical calculations and experimental studies were analyzed and appropriate conclusions were drawn.A formula has been developed to determine the real resistance of the stretched metal reinforcement at the time preceding destruction. The calculation algorithm has been compiled. When comparing theoretical and experimental strength, the difference did not exceed 5%.

Keywords: steel, heavy concrete, reinforced concrete, testing, stand

The structural integrity of many reinforced concrete structures can be broken due to corrosion of reinforcing steel. This phenomenon is quite pronounced in infrastructure where de-icing chemicals are widely used. The aim of this study is to examine the bond characteristics between reinforcing steel and surrounding concrete to evaluate its effect in corrosion. The strength of the bond was studied in terms of elongation load response, cracking behavior.It is shown that the friction between concrete and reinforcement along the edge of the rib prevents the concrete key from sliding relative to the rib. The force due to friction between the reinforcement and concrete at the rib is vectorially added to the cohesion component acting perpendicular to the rib. If friction between the concrete and reinforcement is lost, the only component of bond strength is the force acting perpendicular to the rib. In pullout failure, the friction between concrete and reinforcement is less important than in spalling failure.

Keywords: reinforcement, concrete, bond, slip, sliding, pullout, corrosion, concrete deformation.

One of the main causes of structural failure is fatigue, which is caused by failure under repeated cyclic load. The vibration strength of welded joints depends on the height of the weld catheter, equivalent Mises stresses and general movements of frame assemblies of building metal structures experiencing multi-cycle loading reliability of frame assemblies when they are reinforced.

Keywords: reinforcements, reliability, assemblies, metal structures, multi-cycle fatigue

Increasing the energy efficiency of the construction process involves the use of materials with the lowest material intensity, including thickness, as well as with a reduced content of Portland cement clinker while maintaining or improving the technical characteristics of the products. In this regard, the use of textile concrete products, including concrete sheets, is promising. The development of a composite binder containing components that reduce nega-tive pressure in hardening concrete, and consequently shrinkage deformations and cracking, made it possible to obtain products with the following waterproofness indicators: determined by the ""wet spot"" method: 1.2 MPa; with a filtration coefficient of 5-7×10-11 cm / s; the concrete waterproof grade W12

Keywords: textile-concrete, concrete web, water resistance, shrinkage during hardening, cracking, fine concrete