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Vol. 6 Issue 6

Archives Journal Construction Materials and Products Vol. 6 Issue 6

Structure and properties of modified shungite concrete during electrode heating

https://doi.org/10.58224/2618-7183-2023-6-6-1
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Abstract
Concrete composition modifying by different electrically conductive components is one of less laborious but relatively effective methods between wide variety of electrode concrete heating effectiveness improvement methods. The purpose of this study is investigation of special aspects of cement systems modified by powdered shungite (Ssp 400 m2/kg) in combination with active mineral and plasticizing admixtures that harden under electrode heating at below zero temperatures. By the method of differential thermal analysis anomaly of exothermic reaction of cement stone specimens was discovered, that is due to formation of hydrated calcium silicate С2SH (A) discovered by the method of quantitative XRDA, and is verified by results received from scanning electron microscopy method, which among other factors provides higher strength and low permeability to these composites. Stabil-ity of cement systems modified by shungite and curing under electrode heating has been proved.
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Study of the characteristics of pavement elements made of rein-forced soil with the use of secondary resources

https://doi.org/10.58224/2618-7183-2023-6-6-2
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Abstract
The importance of using secondary resources on the basis of industrial waste is understood by both governments of developed countries and business (production of Portland cement using ground metallurgical slag as a mineral additive at Novotroitsk, Magnitogorsk, Sterlitamak, Katav-Ivanovsk and other plants in the South Urals). The use of secondary raw materials requires the creation of technological infrastructure for processing of secondary raw materials, the costs of which can be quickly recouped due to the cheapness and availability of industrial secondary raw materials and freeing the territory from environmental pollution. In order to recoup the costs of the infrastructure, it is necessary to guarantee full compliance of the quality of pavement elements with the requirements of GOST R 59120-2021. Secondary raw materials have a great variety and laboratory analysis of the quality of pavement elements is required in order to design compositions with the best quality, satisfy-ing all regulatory requirements. In our work the authors present the results of laboratory research and evaluation of the possibility of using clinker-free lime-slag binder based on the mineral product of so-da production and metallurgical slags to strengthen and stabilize soils for their use in pavement struc-tures in the construction of roads for various purposes and climatic zones.
It is experimentally shown that the addition of lime-slag binder in the amount of 8-10% of the dry weight of both cohesive (loamy soil, loamy sand) and non-cohesive (fine sand) soil allows to obtain reinforced soil with improved strength and elastic-deformative characteristics, which can be used in-stead of scarce natural crushed stone and gravel in the construction of underlying layers of pavements in the construction and reconstruction of highways. This technology can be used not only in the Rus-sian Federation, but also in a number of other countries, including those with hot dry climates (e.g., the Republic of Egypt).
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Technology for the production of road bitumen modifier using aluminosilicate microspheres extracted from ash and slag energy waste

https://doi.org/10.58224/2618-7183-2023-6-6-3
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Abstract
The results of research on the development of technological solutions for the production of a new rubber-bitumen binder for asphalt concrete based on the use of industrial waste: used car tires, used car oil and microdispersed aluminosilicate spherical particles obtained from the processing of ash and slag waste (ASW) from thermal power plants are presented. The proposed technological solutions make it possible to obtain high-quality polymer additives for modifying the properties of road bitumen. The elements of novelty of the developed approach include the use, to obtain a granular modifier, of micro-sized hydrophobized aluminosilicate spheres, which are extracted as an additional product during the complex processing of ASW. The positive economic efficiency of technological solutions is ensured by the use of large rubber crumb (more than 8 mm) or rubber chips, their devulcanization together with hydrocarbon fractions of used engine oil and petroleum bitumen at a given temperature to form a gel-like mass, which is further subjected to mechanical grinding in a mill.
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Features of the pyrolysis process of waste batteries using carbon black as an additive in the construction industry

https://doi.org/10.58224/2618-7183-2023-6-6-4
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Abstract
The paper discusses the technology for recycling used lithium-ion batteries. At the same time, one of the important components in the technology for processing such waste is the recycling of anode material with the extraction of graphite or carbon black, which can be used in the production of fire bricks. It has been shown that materials and compounds contained in lithium-ion batteries are sources of hazardous waste of the second hazard class. At the same time spent accumulators are a source of valuable secondary material resources and contain in their composition up to 16 % wt. % of graphite.The paper proposes to consider the process of processing anode materials of lithium-ion bat-teries in order to obtain graphite and carbon black from them by pyrolysis. Experimental studies were carried out on the process of decomposition of cathode and anode materials of lithium-ion batteries separately, as well as their mixture by pyrolysis. When studying the kinetics and mechanism of pyrol-ysis of carbon-containing materials, thermogravimetric analysis of the following materials was carried out: 1) powdered graphite grade GAK-2 (GOST 10273-79); 2) graphite released from the anode dur-ing manual disassembly of the LKIT; 3) mechanically activated powders containing cathode material LiNiMnCoO2. The characteristics of the pyrolysis process were assessed using thermogravimetric and differential thermogravimetric analyses. Pyrolysis characteristics demonstrate that organic substances contained in batteries can decompose at a pyrolysis temperature of 500 °C for cathode materials and 450 °C for anode materials. This subsequently leads to higher efficiency in the extraction of valuable components with shorter grinding times. It has been shown that the decomposition of a mixture of lith-ium-ion battery materials removes a larger amount of organic components than the pyrolysis of anode and cathode materials separately. In this case, the rate of decomposition of the mixture of materials occurs more slowly. The activation energy values for lithium-ion battery materials after the pyrolysis stage were determined. The content of components in powder obtained after the pyrolysis stage was determined using the method of atomic emission spectrometry with inductively coupled plasma.
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Dry mixes on gypsum and mixed bases in the construction of low-rise residential buildings using 3D printing technology

https://doi.org/10.58224/2618-7183-2023-6-6-5
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Abstract
3D-printed building construction technology is developing in most countries, such as France, China, Russia and others, and the dry mixes and equipment used are being improved. The development of 3D-printing construction technology is dictated by its many advantages: architectural diversity, speed and automation of the technological process of construction of buildings and structures with a noticeable reduction in the cost of production. However, there are a number of problems of this technology that are waiting for optimal solutions. The paper proposes solutions to two such problems: firstly, the choice of mixture with gypsum and gypsum-cement binders, ensuring the continuity of the 3D printing process of the building and allowing the construction of buildings up to three floors with sufficient safety margin, high seismic stability, as well as with good heat and noise insulation; secondly, the design of buildings with a rational structural and technological solution of the roof and floor, allowing the interface of these structures with load-bearing printed walls.
Different compositions of dry mixes were tested in a series of field tests of large-sized wall blocks made with the use of a construction 3D-printer and filled with especially light porous expanded claydite, expanded clay concrete or heat-insulating foam gypsum with subsequent testing on press equipment of increased load-carrying capacity (with determination of bearing capacity and deforma-bility of the large-sized block).
When designing low-rise buildings, erected by additive technology, as an optimal design of floors, it is proposed to use frame-monolithic beam structures made of metal thin-walled steel galvanized profiles, filled with foam gypsum mix, providing heat and noise insulation and covered with a thin layer of high-strength self-leveling gypsum mix, providing the necessary structural strength of the floor and, accordingly, the minimum load on the foundation.
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Investigation of the stress-strain state of domical masonry vaults

https://doi.org/10.58224/2618-7183-2023-6-6-6
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Abstract
The results of analytical study of stress-strain state of one of the varieties of vaults erected in various function buildings, i.e. domical masonry vaults covering Orthodox churches, are presented in this article. Due to the ongoing restoration of architectural monuments and religious buildings, as well as in connection with the construction of such facilities as Orthodox churches, the study of stress-strain state of masonry arches and vaults has become especially important in recent decades. Despite the rapid development of new building technologies in the construction of temples, use of these new technologies is shown to be limited and focused on the use of traditional materials. The current level of engineering of building structures with the use of software enables to significantly improve the calculation models and to obtain more reliable results, in particular for the structures under consideration. The domical vault considered herein is formed by wall extensions inclined along a given curve, converging in a horizontal crown under rectangular plan or in one point under square plan. The authors of the article have performed calculations of vaults in both linear and nonlinear formulations, with the results thereunder the forces and deformations of vaults have been analyzed. As a result profiles of vertical pressures and lateral pressures of the vault mounting groups, isopoles of principal stresses, vertical displacements, bending moments and normal forces were calculated.
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Failure criterion for concrete under volumetric stress state conditions

https://doi.org/10.58224/2618-7183-2023-6-6-7
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Abstract
Based on the experiments conducted by the authors, a six-parameter failure criterion for concrete has been developed, which makes it possible to take into account the volumetric stress state in strength calculations of massive concrete and reinforced concrete structures. The developed strength criterion is adapted to a spatial eight-node finite element (solid type) and implemented in the PRINS software. To verify the developed criterion, the work provides a com-parison with both experimental data and calculation results that meet other strength criteria widely used for concrete. Thus, the compression and tension meridians of the developed fracture criterion were compared with experimental data, as well as with the Willam & Warnke criterion and the modified Drucker & Prager criterion with Mohr & Coulomb constants. A comparison of compression meridians shows that in the mode of low hydrostatic stresses , these criteria converge with each other and with experimental data. In the mode of average hydrostatic stresses , the criterion proposed by the authors and the Willam & Warnke criterion show similar results, while the modified Drucker & Prager criterion shows on 20% overestimation of the failure value.
In the mode of high hydrostatic stresses , the Willam & Warnke criterion in com-parison with the proposed criterion and experimental data, gives an underestimated value of concrete failure.
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Assessment of the quality of the urban environment in the process of construction project management

https://doi.org/10.58224/2618-7183-2023-6-6-8
Abstract
Recently, the construction of residential buildings in the Russian Federation has been carried out at an accelerating pace, not only in large cities, but in almost all regions of our country. In the current conditions, the issues of rational planning of residential development within the framework of urban construction development are becoming increasingly relevant. At the same time, an important role is assigned to the methods of assessing the quality of such planning. The analysis of the available methods of this kind carried out by the author indicates that at the moment, there are practically no adequate and objective methods for quantifying the degree of accessibility of critical social infrastruc-ture facilities of the city in relation to newly constructed or already existing residential buildings.
Based on the results of the applied research carried out within the framework of writing the pre-sented scientific work, the author proposed an innovative method for quantifying the degree of acces-sibility of socially significant urban objects relative to residential structures. The proposed methodolo-gy is unique in that, thanks to the use of such a universal and statistically accessible indicator as the average level of wages, experts have the opportunity to conduct a comparative assessment of the de-gree of accessibility of social objects, not only located within a walking distance, but also at longer distances, involving the use of public passenger transport.
The application of the methodology proposed in the framework of writing this applied scientific work for assessing the quality of the urban environment for the accessibility of socially significant in-frastructure objects relative to the location of residential buildings will allow, on a mathematically ac-curate quantitative basis, not only to assess the effectiveness of the work of regional state authorities and local self-government as qualitatively and objectively as possible, but also to conduct a compara-tive analysis of the quality layouts of newly designed residential neighborhoods. In addition, this tech-nique may be of practical interest to realtors and developers in the development and practical imple-mentation of various types of business processes, both in the field of housing construction and in the sale of residential buildings and premises.
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Vernacular architecture in the space of a modern city, based on deep learning methods and three-dimensional structural analysis

https://doi.org/10.58224/2618-7183-2023-6-6-9
Abstract
This research paper describes the process and results of a project to automatically classify historical buildings using aerial photography and satellite imagery. New computational scientific methods and the availability of satellite images have created more opportunities to work on automated recognition of pieces of historical architecture. In this regard, the convolutional neural network (CNN) is the main classification approach within the project. As a result, the trained model is tested using a validation data set and has a roughly 98% accuracy. In addition, being affected by urbanization and other factors, local architectural heritage faces the challenge of introducing innovations for sustainable development, with originality and authenticity being preserved in redesign and planning. Thus, this study uses a visualized quantitative analysis to analyze the research trends in Russian vernacular architecture and study new ways of coexistence between vernacular architecture, object perception and cultural ecology. The most important task of this study is to analyze the theory of coordination between the emotion social and cultural structure and the cultural ecosystem in vernacular architecture. The main contribution of this study is the proposed concept of a subjective-cultural eco-design system for vernacular architecture sustainable development to establish a 3D structural analysis design paradigm and evaluation analysis matrix, and to ensure that vernacular architecture demonstrates the ability to self-renew by continuous exchange and revision in the dynamic cycle of the current design system.
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