Designing foundations and foundations for buildings and structures of high-rise complexes is a complex engineering task. Modern architectural concepts and constructive solutions should be based on geotechnical justification at the stage of developing the architectural design of the project. Huge loads from above-ground structural elements of high-rise buildings and the high cost of measures for the installation of underground structures create their own characteristics in the design of foundations. In this paper, we study the problem of choosing the type of foundation for a high-rise building from the point of view of technical and economic rationality based on studying the experience of designing complex multifunctional complexes in Moscow and St. Petersburg. The authors believe that the choice of a constructive solution for the foundation of a high-rise complex is influenced by both geological factors and socio-economic ones. The result of this study is the grouping and systematization of the geotechnical factors of the building area and the economic factors of the urban environment that directly or indirectly affect the construction projects of high-rise complexes.
Keywords: high-rise complexes, slab and pile foundations, combined foundation, RIT-piles, geotechnical calculation, geotechnical monitoring, geotechnical factors, socio-economic factors, rational choice
The calculation of statically indeterminate structures, such as a two-span reinforced concrete beam in an elastic formulation does not reflect the actual force resistance, therefore, calculations of such structures are performed taking into account the occurrence of plastic deformations and the formation of plastic hinges, and the presence of local corrosion damage to concrete and reinforcement determines other dependencies of the redistribution of forces in the bent elements. The numerical calculation of 14 models with various corrosion damages along the length of the beam is performed. The dependence of the increase in deflections on the percentage of corrosion damage at various stages of loading is presented. The dependences of the redistribution of emerging forces in the span and supporting parts of a two-span beam on the percentage (length) of corrosion damage are shown. It was found that with 1% of damage at the initial stages of loading, there is a jump of tensile forces in the armature located in the span of the beam. It is determined that the greatest redistribution of tensile forces in the supporting part of the beam, which has 50-70% corrosion damage, is 11%.
Keywords: reinforced concrete beam, redistribution of forces, plastic hinge, corrosion of reinforced concrete, numerical calculation, bearing capacity
The lack of water resources determines the problem of their rationing. Existing water consumption standards provide for a wide range of daily consumption values. This does not take into account possible measures to save water, provided for by the concept of buildings with a zero balance of water consumption. In addition, the technical specifications for the design of water supply systems include, for economic reasons, the smallest possible number of residents. The actual occupancy may exceed the planned one by several times, which requires further investment of additional funds already in the reconstruction of the newly built network. The objective of the study is to develop an analytical model of water consumption, the analysis of which allows us to evaluate the dynamics of changes in the specific water consumption with a variable population.
Keywords: specific water consumption, indifference curves, resource replacement rates, marginal water consumption
The article deals with the analysis of the formation of a public center in military camps, including the analysis of towns in various military districts, as well as the estimated number of military camps.
Keywords: military camps, standard building projects, public buildings, numbers, cooperation
Currently, one of the most promising and cost-effective methods of seismic isolation is the use of passive energy dissipation systems. The research carried out in this article focuses on the use of a new hybrid energy dissipation device that combines a parallel layer of an inexpensive viscoelastic material and a metal component. Typically, the viscoelastic material in such systems is attached to steel shock absorbers with an adhesive. In this article, the behavior of a viscoelastic material is studied when it is attached to a metal component without the use of glue, being held only by friction and pressure. The influence of the compression force on the elastic and damping properties of a viscoelastic material arranged in a seismic damper has been established, and the pressing force has been determined, which ensures the optimal functional properties of the viscoelastic material.
Keywords: earthquake, seismic safety, damper, thermal expansion, viscoelastic material, rubber compound, rubber, resin, polymer, vibration, seismic isolation
The article presents studies of the monument of the Middle Ages of the VII- VIII centuries the fortress of Khashupse (Abkhazia), the features of its planning organization. The scientific novelty of the article is that a detailed study of the Hashupse fortress is being conducted for the first time.
Keywords: fortifications, planning organizations,medieval architecture of Abkhazia, fortress
An engineering technique for determining the bearing capacity of reinforced bending elements of building structures made of a binary composite material with a multi-modulus, nonlinearly elastic polypropylene matrix and powder filler is described. Information about various approaches to solving the problem proposed by other researchers is given. The author's method for obtaining the predicted physical and mechanical characteristics of binary composite materials is described, which gives more accurate results compared to known approaches. An algorithm for iterative refinement of the geometric characteristics of structural elements with an arbitrary cross section and a non-linearly elastic matrix has been developed. A computer program is described that automates the process of characterization, examples of specific cross sections are given. The possibility of refining the geometric characteristics of elements in the direction of their increase is proved.
Keywords: composites, matrix, filler, non-linear elastic material, armature, iterative process, computer program, beam, I-beam, geometric characteristics
The article compares the principles of architectural designing industrial enterprises, which were fixed in the 70s - 80s of the twentieth century, and modern ones associated with changes in socio–economic relations in the XXI century. The specifics of the approach to the architectural design of large and small enterprises are described. Special attention is paid to the influence of economic factors on the industrial architecture of small enterprises, the importance of the time factor. The most acute problems that arise today in the architectural design of small enterprises are identified, and ways to solve them are proposed. A new functional element of the general plan of an industrial enterprise is described - the "development zone".
Keywords: Iidustrial architecture, principles of architectural design, functional zoning, "flexible" planning solutions
An engineering technique for predicting the main physical characteristics of multicomponent composite materials with a polypropylene matrix is described. The technique is based on the calculated dependences obtained for a binary composite. Calculation formulas for determining the modulus of elasticity and Poisson's ratio of an artificial material are given. An algorithm for applying the proposed formulas is described, which consists in successively obtaining the desired characteristics, each time considering a two-component composite and taking as the initial material a composition of a polymer matrix and one of the fillers. A specific example shows that the order in which fillers are taken into account does not affect the final result. The proposed technique can significantly reduce the design time for new materials and will make it possible to reduce the number of real experiments. The difference between the theoretical results and the data of physical experiments does not exceed 10–15%.
Keywords: composites, matrix, filler, polypropylene, wood flour, chalk, modulus of elasticity, Poisson's ratio
The presented article deals with flat roofs of triangular trusses with the development of the structural form in one longitudinal direction. Bearing structures of trihedral trusses are used for public and industrial buildings and constructions. Using the modular system as a result of cross structural division of the structures of triangular trusses allows to carry out their safe transportation to the place of storage or construction. The peculiarities of formation of the modular system taking into account structural peculiarities of the layout of spatial trihedral trusses are considered. By the results of a comparative analysis of the deformability of mathematical computational models of three-sided trusses in the roof, the use of pliable module coupling assemblies was substantiated. The possibility of using different element composition of rods within each module of a triangular truss is confirmed.
Keywords: modular system of a trihedral truss, structures of non-centered truss-less knots; spatial-string computational model; deformability of modular systems with rigid and compliant mounting knots, comparative analysis of computational models
Technical and economic peculiarities of construction and exploitation of these unique buildings should be considered during the project. One of the peculiarities are the ability to save city´s space, to be main architectures of the city. The most important organizational economic targets of a diversification of management are presented by innovative activity of the industrial enterprise.
Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production
Based on available literary and photographic sources, the architectural, spatial and planning methods of reconstructing railway stations into transport interchange complexes are analyzed and the main ones are identified. The conclusion is made about the most important methods of reconstruction from a functional and planning point of view, which allow transforming stations into modern transport interchange complexes.
Keywords: transport interchange complex (TPC), transport system, transport complex, railway station, railway station, transport junction, railway junction, modernization of the station, reconstruction, reconstruction of the station, methods of reconstruction
Dependences of strength and deformation properties of heavy concrete under early loading under conditions of negative temperatures are obtained on the basis of experimental data. Empirical coefficients are proposed to describe the measure of concrete creep through the temperature function. A significant increase in the strength of concrete hardening under load during freezing and thawing has been confirmed. The results can be used to assign the parameters of early loading and calculation of monolithic buildings at the stage of their construction.
Keywords: monolithic buildings, building structures, heavy concrete, strength, deformation, creep, creep measure, early loading, loading intensity
The article deals with the structural forms of spanning trihedral trusses used as load-bearing structures of flat roofs of buildings and structures of various purposes. An algo-rhythm for arranging tubular belt bars from rolled elements with layout conditions for a channel and an angle is presented. Based on the results of numerical studies, the stressed elements of the spatial strut system have been determined. Also, based on the results of the comparative analysis of the deformability of the computational model of a triangular truss, the application of prestressing with a mechanical tensioning device on the stops in the ends of the lower longitudinal rod has been substantiated.
Keywords: prestressed trihedral truss, compound profiles of longitudinal cores, non-centred nodes, spatial-core design model, schemes of application of nodal design loads, deformability, evaluation of numerical results
This article is devoted to finding the key geometric characteristics of circular arches by graphical and analytical methods. Also in this article, algorithms for solving the problem of finding geometric characteristics by graphical and analytical methods are analyzed and these methods are compared in terms of speed and ease of use. Today, you can solve geometric problems in numerous graphic editors. Such editors allow you to quickly calculate the necessary geometric characteristics of any design, for this it is enough to draw a drawing in the software package, the required data will be obtained automatically. However, there is another method for solving such problems, for example, using formulas. This method is based on the principle of an algorithm or a sequence of formulas, thanks to which it is possible to obtain unknown characteristics by setting known characteristics, as well as to solve the inverse problem. Also, this method allows you to create software based on the algorithm, which will greatly simplify and speed up the solution of such a task. The purpose of the research described in this article is to create an algorithm for solving problems of finding geometric characteristics of a circular arched structure according to known mathematical formulas, followed by the implementation of this algorithm by programming tools in Excel.
Keywords: arch, geometry, calculation methods, rectilinear segments, rotation angles
The problems of modern methods of building construction, namely the obsolescence of construction technologies and the production control system at most facilities under construction do not provide the required level of quality. Due to low-quality materials, formwork, reinforcement, laying and ramming, defects and deviations from the most important requirements for the finished product appear and resource costs increase significantly. Therefore, in order to develop and introduce effective measures to improve the existing methods of building construction, this paper lists the main disadvantages of the technologies used. The practice of applied innovative technologies that can increase the quality and speed of the structures being built is given. The technologies of erecting buildings using various fixed formwork designs are considered.
Keywords: sound insulation, shock noise, residential buildings, noise insulation, air noise, monolithic house, comfortable environment, noise, construction, materials
The main features and goals of energy efficiency in residential construction are considered in order to ensure minimal heat loss of buildings, and thus reduce the use of the required amount of energy to compensate for heat losses. With the increasing energy crisis and the deterioration of the environmental situation in large cities, recently foreign countries have attached importance to the rational use of energy resources. Facades are one of the main elements that provide a solution to improve the energy efficiency of the building itself, as they reduce the heat loss coefficient to a significant level. Today, Germany is a world leader in energy efficiency, as the country uses the most modern energy saving technologies. The technology of using energy-efficient facades in Europe is already considered normal and at the moment the technology of using a ventilated facade, translucent facade system, "green facade", dynamic facade represent more progressive solutions to improve energy efficiency.
Keywords: energy efficiency, heat loss, enclosing structures, facade, foreign experience, hinged ventilated facades, translucent facade system, green facade, dynamic façade
The main recommendations for the installation of a gas pollution detector in domestic premises are considered, an experiment is conducted using the Altair 4x gas analyzer, the purpose of which is to determine the concentration of the gas-air mixture at various points of the household relative gas source. The data obtained experimentally is analyzed, which results in a formula that allows you to determine the approximate concentration of the gas-air mixture, I only know the measurement time and height relative to the ceiling to the measurement point. Also, this formula allows us to note that when choosing the installation location of the gas pollution detector, attention should be paid to the distance from the ceiling to the installation point of the device, while the distance from the wall to the installation site of the device plays a less important role when a gas leak is detected by the device.
Keywords: gas pollution detector, gas-air mixture, gas concentration, emergency shutdown, lower concentration limit of flame propagation
The article analyzes the technical condition and reliability of heat supply networks. When using the calculation and assessment of the overall reliability of pipelines and sources of heat supply. Substantiates the requirements for the reconstruction of regular pipelines.
Keywords: heat supply, reliability of the heat supply system, hydraulic calculation, reliability coefficient, dilapidation of the heat supply network
Currently, lighting systems with hollow tubular light guides that can transport light to any part of the building have been widely used for natural illumination of buildings. The article presents a comparative analysis of the operation of hollow light guides and traditional side and upper light openings. Examples of large realized projects of buildings with hollow tubular light guides in Russia show the rationale for choosing such lighting systems and their advantages. The unique experience of using light guides for natural lighting of a church in Siberia is considered in the paper. During the design of this illumination system some innovative technical solutions were developed and implemented for the first time. The access of daylight in dark rooms, the provision of thermal and light comfort in the building, energy saving, protection from adverse weather conditions, the emergence of new opportunities for architectural solutions are factors determining the prospects for application of a natural lighting system with hollow tubular light guides in Russia.
Keywords: natural lighting systems, hollow tubular light guides, side and upper light openings, energy saving, innovative technologies
The problem of choosing the most optimal gas supply scheme for rural settlements is considered, taking into account technical and economic criteria. For example x. Knyazhensky-1, Mikhailovsky district of the Volgograd region, several gas supply schemes are proposed. The feasibility study of the choice of one of the possible options is given. It was found that for rural settlements with an extended form, the most optimal is a scheme with two sources of gas supply and a reserving jumper between them.
Keywords: gas distribution network, gas reduction points, hydraulic regime, normalized pressure, cost, construction and installation works
The use of clayey soils in the construction of subgrade allows to reduce the use of sandy soils, thereby reducing the number of quarries formed. However, this requires the implementation of constructive measures aimed at ensuring reliability, strength and safety. One of the ways to implement such activities is the use of geosynthetic materials. In the article, based on the experience of designing and building objects with geosynthetic materials, the criteria for choosing their types depending on the tasks being solved are established. The necessity of developing a mathematical model substantiating the decisions taken is considered. The obligatory organization and conduct of geotechnical control is noted as a tool to determine the directions for the development of this area of construction in order to reduce the technogenic load on the territories associated with the withdrawal of natural resources.
Keywords: subgrade embankment, transport engineering structure, geosynthetic material, embankment reinforcement, anti-erosion protection, geotechnical control
Significant climatic changes are currently observed in the Arctic zone of the Russian Federation, the intensity of which is 2.5 times higher than the average planetary level. The continental and shelf zones of the Arctic region of the Russian Federation contain a significant amount of minerals, including hydrocarbons. The cost of extracting this raw material on the mainland of the Russian Federation is becoming more expensive due to the depletion of existing deposits. In connection with this and the observed climatic changes, the Government of the Russian Federation has begun active development of this region. The development of the Arctic region is associated with the construction and reconstruction of port hydraulic structures included in the Northern Sea Route, the expansion of port infrastructure and the construction of terminals for liquefied natural gas. The current construction regulatory documentation of the Russian Federation does not provide for accounting for changes in wave, ice and hydrostatic loads on port hydraulic structures during their operation due to projected climatic changes in the region. The issue of the need to take into account climatic changes in the design of port hydraulic structures in the Arctic zone of the Russian Federation is considered. Conclusions are drawn that taking into account climatic changes will reduce the cost of major repairs during the life cycle of structures and reduce the risks of accidents caused by the operation of structures under design loads.
Keywords: climate change, construction projects in the Russian Arctic, port hydraulic structures, western Arctic
The construction of public buildings from a metal frame is always associated with the search for a rational constructive solution that meets not only the dependability requirements, safety, but also architectural and design solutions. Often, the solution to the problem of rationalization of roof construction in public buildings is the use of arched combined systems, since such systems have a number of advantages over simple arches: the survivability of combined systems is higher than simple ones, the possibility of creating complex, architecturally expressive spatial structures, lower material consumption, high load-carrying ability with relatively low weight, etc. The aim of the research is to find a rational construction solution for two arch-cable systems (Hud type system and Radial type system) by comparing in terms of the minimum internal forces, displacements and metal intensity at different ratios of the arch boom and span. Based on the calculation results in the Lira SAPR 2020 software, the most unfavorable loads combinations were determined, deformation schemes of arch systems, displacements, moments and forces were obtained, sections of arches and ties were selected. From ten arched structures of two types considered with different ratios of arch boom to span, the Hub type system with the ratio of arch boom to span f/L = 1/3 and Radial type system with the ratio of boom to span f/L = 1/4 showed the best result in terms of efficient operation and metal intensity.
Keywords: combined systems, arch-cable constructions, simulation of prestress, hub type s
Increasing the energy efficiency of panel houses of mass development in the territory of the Republic of Khakassia is an urgent problem, since typical panel buildings make up the majority of the housing stock of the Republic. The purpose of the study is to find the most effective design solution that minimizes heat loss through the enclosing structures. The paper presents a thermal imaging survey of a panel residential building located on the territory of the region, identifies the main areas of heat loss. The analysis of calculations of structural coupling units performed by the finite element method in the Elcut Professional software package is carried out. The most effective version of the wall construction to reduce heat loss has been proposed.
Keywords: energy efficiency, heat loss, exfiltration, infiltration, building inspection, thermal imaging inspection, enclosing structures, panel five-story houses