Archives

Big Data in Predicting the Climatic Resistance of Building Materials. I. Air Temperature and Humidity

https://doi.org/10.58224/2618-7183-2023-6-3-18-30
Abstract
The article provides a comparative analysis of the quantitative values of temperature and relative humidity of the ambient air calculated according to GOST 16350-80 for a moderate continental climate (representative location – Moscow), and obtained at the meteorological station of Ogarev State University (Saransk) for the period from 2015 to 2022. A significant discrepancy between the calculated and accumulated values of meteorological factors has been established. In the studied time interval, the spread of the difference between the calculated and accumulated values ranged from -5.8 to 10 oC for air temperature and from -36.4 to 32.5% for relative humidity. There is also a significant variation in the difference of the studied indicators depending on the calendar month, as well as a de-viation of a number of distribution curves from the normal form, which, in general, indicates the im-possibility to reliably assess distributions using only the value of the quadratic deviation recommended by GOST 16350-80. It has been established that the use of calculated distributions virtually does not allow taking into account events occurring near the boundaries of the distributions of the studied me-teorological parameters. This, in turn, irreversibly affects the accuracy of forecasting the climatic aging of building materials. When predicting the climatic resistance of materials by machine learning methods, it is proposed to use absolute humidity values instead of relative humidity as a sign that has a clear physical meaning (mass of water vapor contained in 1 m3 of air), as well as defined only in the range of non-negative values.
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Three Bimoments Equation of V.I. Slivker’s Semi-Shear Theory for the Calculation of Multi-Span Thin-Walled Beams

https://doi.org/10.58224/2618-7183-2023-6-3-31-46
Abstract
This article discusses the method of static calculation of multi-span thin-walled beams with bending torsion in the framework of the semi-shear theory of V.I.Slivker. The main advantage of the semi-shear theory is that it is suitable for rods of both open and closed (as well as open-closed and multi-contour) profiles due to the similarity of differential equations according to the theories of V.I. Slivker and A.A. Umansky, and also increases the accuracy of the calculation due to taking into account part of the shear deformation. The analytical solution of the problem is obtained based on three bimoments equations system of, including values of correlating functions for cases of application of torsional loads in the span and on the cantilever of thin-walled multi-span continuous beams. Bimoment func-tions for a number of simple beams are obtained within the framework of the semi-shear theory. It is shown that the values of the parameter of the influence of the shape of the cross-section of the semi-shear theory ranges from 1.000086 to 1.0014 for channel profiles, while the presence of shelf bends (C-profile) in comparison with the channel profile reduces the value of this parameter by 10%, which indicates a lower contribution of part of the shear deformations to the stress strain state at the torsion of the C-profile. It is shown that, despite the convergence of the calculation results by the proposed method, due to the proximity of the values of the shape influence parameter to 1.0 with the similar one according to the theory of V.Z. Vlasov, the area of application of the proposed method are significant-ly wider (both open and closed profiles).
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ESG-security of Urban Economy in the Concept of Sustainable Development

https://doi.org/10.58224/2618-7183-2023-6-3-47-58
Abstract
The article considers the importance of ESG-security of the urban economy, reveals the relevance of this area of research, analyzes foreign and domestic environmental standards. Also, an analysis was made of the use of certification in the Russian market, the territories where "green" objects predominate were considered, and it was also considered what results "green" construction brought to these objects. Within the framework of scientific work, an analysis of the attitude of the state to envi-ronmental safety was carried out using the developed standards and national projects as an example, and improvement measures were proposed.
The development of cities is accompanied by constant construction. This development cannot be stopped; accordingly, it is impossible to stop the expansion of territories through construction, which in one way or another implies an impact on the environment. But this impact can be minimized and balanced with the help of "green" building. It will help reduce the risk of environmental pollution and the negative impact on the person himself. Understanding the need to create ESG security will help prevent an environmental crisis.
Awareness of the state of ecology today is present both among the population and the state, which is a positive trend on the way to improving the environment and people's lives. Despite the fact that this understanding has appeared relatively recently, it is actively gaining popularity abroad and in Russia, however, it must be instilled, including in the population at the regional and local levels, and not only in large cities. It must be learned that the use of environmentally friendly consumables in construction will help create a better future for us and future generations, without requiring large investments.
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Ecological Safety of Construction in Single-Industry Town

https://doi.org/10.58224/2618-7183-2023-6-3-59-78
Abstract
Ensuring environmental safety during construction works is an important condition for the sustainable development of single-industry towns. The high rate of urbanization, population growth of single-industry towns and their active construction leads to negative anthropogenic changes in the en-vironment, which negatively affects both the ecology and the life of the population of a single-industry town. In this article the basic factors of the influence of the sphere of construction on the environment are considered, the aspects of providing ecological safety during construction are investigated, the normative-legal base regulating these aspects during construction works is analyzed, and also possible approaches and measures to decrease the negative influence of construction on the environment in monotowns are given.
The article proposes measures to reduce the negative impact on the environment and improve envi-ronmental safety of construction in single-industry towns, such as complementing the existing legisla-tion with stricter standards and requirements to ensure environmental safety during construction work in single-industry towns, development and active implementation of modern environmental materials and technologies, strengthening environmental control mechanisms of the construction sphere in sin-gle-industry towns and raising awareness of business and population. The article was prepared based on the results of research carried out at the expense of budgetary funds under the state assignment of the Financial University.
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The Planning of Intra-Block and Open Urban Spaces in the Historic Environment of the City: a Socio-Managerial Aspect

https://doi.org/10.58224/2618-7183-2023-6-3-79-97
Abstract
Urban space is a system of open architectural spaces with elements placed in them. However, the purpose of their organization is not limited to the creation of a network of building-free spaces, it is also to meet the needs of society. This applies without exception to all types of urban space of different public purposes.
The aim of the article is to illuminate the socio-managerial aspects of the planning of intra-block and open urban spaces in the historic environment of the city.
The paper defines the terminology and analysis of the formation and development of existing intra and open urban spaces of the historic part of the city with the definition of their functions. The analysis of the main problems of intra and open urban spaces in the historic development of the city and the ways of their solutions proposed.
The article concludes that the priority task of planning of inner and open urban spaces in the historic environment of the city is not only the design of the various elements, but also the study of the city in its potential development, the rethinking of its nature to create new properties and characteristics of urban space, where the dominant matter is the individuality of environment, namely the historically established area.
The results of the study can be used in the practice of reconstruction of urban spaces in the historic part of the city.
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Regional plans for solid waste management: Distinctive features of practice in Russia and EU countries

https://doi.org/10.58224/2618-7183-2023-6-3-98-118
Abstract
Effective management of municipal solid waste (MSW) is a comprehensive problem that appears among the highest priorities on the global environmental agenda. In 2015 and 2022, a landfill filtrate was studied at a landfill for the disposal of solid household waste in the Leningrad region (Russia) to determine the content of various chemical and toxic substances. By comparative analysis of the monitoring results, it was revealed that landfill soil is extremely dangerous. The excess of the maxi-mum permissible concentrations of heavy metals in the filtrate ranged from 2.5 to 67.5 times. This paper presents the results of the analysis of landfill filtrate taken in 2022 from sanitary protection zones and compared with previous data. It was found that the danger associated with the landfill of municipal solid waste is that chemical and biochemical processes occurring between the various com-ponents of landfill filtrates lead to the formation of toxic compounds and are a source of infectious infections. Regional differences and a shortage of effective international instruments often hinder the solution of this problem, making it difficult to develop and apply innovative mechanisms. These con-ditions act as determining factors in the development of state programs for socio-economic develop-ment, particularly in Russia. Political and legal initiatives that have been adopted, in particular those that are part of nation-scale projects, have not yet received impulses for full-fledged practical imple-mentation.
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Experimental studies of the processes of structure formation of composite mixtures with technogenic mechanoactivated silica component

https://doi.org/10.58224/2618-7183-2023-6-2-5-18
Abstract
The paper considers the issues of utilization of technogenic fibrous material – waste of basalt production. The chemical composition of the technogenic fibrous material was studied, it was found that it consists of 44% SiO2. The initial basalt rock, which undergoes changes during high-temperature processing in the process of obtaining basalt fiber, was studied using IR spectroscopy. The grinding of the crowns was carried out for 30 minutes, allowing to reach a specific surface area of 800 m2 / kg. Further grinding does not lead to an increase in the specific surface area, which is associated with the phenomenon of secondary aggregation of fine particles. Research on REM has shown that the “cold shots” before grinding are mostly rounded or oval in shape. The compositions were formed and the strength characteristics of the samples for the 3rd and 28th day were determined. The maximum strength gain of 59 MPa was established at the age of 28 days in samples with the addition of 5% ground “cold shots” . When introducing cold shots in an amount of 10% (composition 5) of the cement mass, an intensive strength gain is noted in the early stages of hardening (7 days) with a strength of 38 MPa, slightly higher than the strength of the control composition. The introduction of 15% ground “cold shots” gives a strength value slightly lower (32 MPa) than the values of the control composition (37 MPa) at all stages of hardening.
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Efficient Silicate Composites of Dense Structure using hollow microspheres and Unconventional Aluminosilicate Raw Materials

https://doi.org/10.58224/2618-7183-2023-6-2-19-34
Abstract
One of the urgent tasks in the field of building materials science is to provide the construction complex with various types of environmentally friendly, reliable and energy-saving materials, the production and use of which will contribute to solving the problem of anthropogenic impact on the environment through the use of little-used technogenic raw materials. In the current conditions of import substitution, it is necessary to use the existing technological base to increase the volume of production of affordable, highly efficient, environmentally friendly traditional building materials, including using the existing raw materials base of the regions. In the market of building materials, structural wall materials of hydration hardening obtained using Portland cement as a binder are widely represented. However, silicate materials occupy not a small market share. It is known that pressed silicate materials of dense structure have fairly good strength indicators, but their thermophysical characteristics are low. A decrease in the average density of dense silicate products can be achieved by introducing various pore-forming components, such as hollow microspheres, into the raw material mass. The paper shows that the use of hollow aluminosilicate microspheres in the technology of obtaining silicate materials of dense structure based on unconventional aluminosilicate raw materials with energy-saving parameters of autoclave synthesis (water vapor pressure 0.4 MPa) and under conditions of heat and humidity treatment at atmospheric pressure allows to obtain a building composite with improved thermophysical and acoustic properties. Introduction to the raw mixture of aluminosilicate microspheres in the amount of 10-60 wt. % allows you to reduce the value of the average density index to 45%. The value of the compressive strength index of such samples, depending on the composition and hardening conditions, is 7-21.5 MPa at their average density of 920-1610 kg /m3, respectively.
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Influence of dynamic loads on fatigue strength of steel beams reinforced with carbon fiber

https://doi.org/10.58224/2618-7183-2023-6-2-35-46
Abstract
The paper evaluates the strength and fatigue characteristics of reinforced damaged steel beams using composite materials – fiber reinforced polymers (FRP) using an analytical model using the ANSYS program. An approach to design based on the methodology of a constant fatigue schedule is considered; models of five steel beams reinforced with carbon fiber are constructed in the ANSYS program. The model was loaded with a symmetrically located concentrated load until destruction. Fa-tigue crack propagation curves have shown that carbon fiber plates restrain crack growth and increase durability. The results showed that carbon fiber reinforcement of steel beams increases the ultimate load and increases the plasticity of the beam.
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Bridge construction in cramped urban environments

https://doi.org/10.58224/2618-7183-2023-6-2-47-57
Abstract
This article discusses the specifics of the construction of bridge structures in cramped conditions of dense urban development. The classification of bridge structures and features of each type are given. The main characteristics and weight and size parameters of elements of bridge structures, methods of their erection, transportation and installation are considered. Particular attention is paid to the arrangement of the construction site, transportation of finished products and materials to the construc-tion site, as well as measures to prevent damage to buildings, structures and transport routes adjacent to the construction site, including the railway.
The study considered the project for the implementation of the construction of the Strela overpass in the city of Tyumen. Emphasis was placed on the production of radial prestressed reinforced con-crete beams of span structures in construction conditions. It was decided to manufacture these struc-tures at the work site.
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