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Utilization of serpentinite waste for the production of magnesium compounds

https://doi.org/10.58224/2618-7183-2025-8-5-8
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Abstract
The article presents the results of research on the complex processing of powdered man-made serpentinite waste formed during the enrichment of chrysotile raw materials in order to obtain high-purity magnesium compounds and assess the potential of their use in the production of building materials. The relevance of the work is due to the need to dispose of accumulated waste and expand the raw material base for the construction industry within the framework of the principles of circular economy. The developed technology includes the stages of acidic leaching of magnesium from PTW with sulfuric acid, neutralization and purification of the solution using thermally activated PTW (TA-PTW) and subsequent precipitation of the target products. It was found that thermal activation of waste at 750 °C leads to dehydroxylation and the formation of highly reactive phases, forsterite and periclase, which significantly increases their sorption activity. The optimal leaching regime is recognized as the use of 0.7 stoichiometrically normal amount of H₂so₄, which makes it possible to extract 82.5% of magnesium from the amount of acid introduced into the solution. The combined use of the initial and thermally activated PTW provides a degree of magnesium extraction of 52.3% of its total content in the system and effective purification of the magnesium sulfate solution from impurities of iron, aluminum, chromium and nickel. Sequential precipitation from the purified solution made it possible to obtain high–purity magnesium hydroxide with a calcium content of 0.0110%, and its subsequent calcination - magnesium oxide with a calcium content of 0.0187%. Special attention is paid to the prospects of practical application of synthesized compounds in the construction industry. It is shown that magnesium sulfate can be used as a modifying additive in cements and as a sealer for magnesia binders. Magnesium hydroxide is an effective flame retardant filler, and magnesium oxide is the main component for the production of flame–resistant and moisture-resistant magnesia binders and plates such as glass-magnesium sheets. Thus, the work demonstrates not only the technical feasibility of highly efficient processing of serpentinite waste, but also the significant resource potential of the resulting magnesium compounds for creating modern building materials with improved performance characteristics.
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Involvement of concrete internal potential to reduce portland cement consumption and ensure sustainable development

https://doi.org/10.58224/2618-7183-2025-8-5-9
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Abstract
Protection of artificial human habitat from negative impacts of external environment and extension of service life of building structures become priority tasks of structural concrete improvement. The most important vector of development is the increase of their strength due to involvement of the internal resources with minimal use of additional external ones, which corresponds to the sustainable development concept. However, practice shows that now application of high-strength concretes, which are the main focus of researchers, is very limited due to insufficient development of production infrastructure, regulatory documentation, design and construction methods, economic and other reasons.
At the same time, approximation to requirements, according to the sustainable development concept, for the most widely used concretes with grade strength classes (B20-B50) is required right now. In this regard, the idea of application of the most important principles of obtaining high-strength self-compacting concretes in the manufacture of medium strength material is relevant. The article presents the main stages of research on development of the design methodology of medium strength classes self-compacting concretes with reduced Portland cement consumption.
The methodological basis for designing these concretes is the successive introduction of additional components principle while recording their effect on the material properties. The use of ground quartz sand as a mineral additive is due to the concrete mix stability requirements and its widespread availability, which allows for the practical application of the obtained results with minimal barriers and contributes to the reduction of CO2 emissions. It has been established that when selecting sand fineness of 180...220 m2/kg and a fixed amount of active mineral additive (7.5%), the compressive strength of the cement paste can be reduced to the following linear dependence: Rbinder28 = 118.9 – 0.22CM. Rational contents of fine and coarse aggregates have been identified, and their quantitative effect on the strength of the resulting concrete has been established. It has been established that the obtained concretes with increased efficiency of Portland cement using can be used in practice in various construction areas, and are also necessary for the search and transparent monitoring of the influence of others, more reactive mineral additives based on industrial products and rocks.
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Application of multi-criteria evaluation methods to create urban development opportunities within the concept of sustainable architecture of buildings and urban areas

https://doi.org/10.58224/2618-7183-2025-8-5-10
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Abstract
The advancement of urban development has made it possible to improve the quality of infrastructure and the organization of urban territories, affecting cities’ competitiveness and investment attractiveness. The study aims to apply multi-criteria evaluation methods to create urban development opportunities in the sustainable architecture of buildings and urban areas. The primary data collection methods include document analysis and an expert survey. Through document analysis, the authors identify the basic methods of evaluating buildings and architectural objects to establish compliance with the requirements of sustainable architecture. The expert survey results highlight the most dynamically developing and globally recognized methods: LEED and BREEAM. Further analysis sheds light on the specific features of criteria-based evaluation of buildings under LEED and BREEAM certification, compares the lists of building evaluation criteria in BREEAM and LEED, and considers the practical implementation of LEED and BREEAM building certification while highlighting and describing architectural objects. The authors conclude that the standards defined in the BREEAM and LEED multi-criteria methods exhaustively conform to the principles of sustainable architecture, encompassing environmental, economic, and social conditions. BREEAM and LEED can be applied to new and modernized residential and public buildings.
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Opportunities for environmentally sustainable development of low-carbon technologies in cement production

https://doi.org/10.58224/2618-7183-2025-8-4-1
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Abstract
In the context of the transition to a low-carbon economy, the development and implementation of environmentally sustainable technologies in cement production is becoming a key priority. Therefore, the development of new binding materials with reduced clinker content or no clinker at all is becoming a key area for reducing the carbon footprint in construction. Use of clinker-free binders, such as geopolymers and various equivalents based on mineral additives, can significantly reduce the carbon footprint of the construction sector in the environment. The most promising and appropriate benchmark is the disposal of industrial waste of aluminosilicate oxide composition with subsequent mechanical and alkaline activation. For the first time, the microstructure of geopolymers based on aspiration cement dust and tuff has been comprehensively studied. The theoretical prerequisite for the creation of a binder system of such a concept is the synthesis of sufficiently strong and resistant to external manifestations of alkali metals, including the structures of frame aluminosilicates with a hidden crystalline structure. The results of a comprehensive study (X-ray phase analysis, scanning electron microscopy, electron dispersion spectrometry, differential thermal analysis and IR spectroscopy) indicate the presence of characteristic hydration reaction products in the geopolymer paste. The following have been identified in the composition of the material: hydrated aluminosilicates; aluminates; silicate groups of sodium and calcium; mineral phases (quartz, calcite); feldspars of the albite-orthoclase series; micaceous components, etc. The data obtained confirm the typical composition characteristic of the processes of structure formation in geopolymer systems. The results obtained on the key results of the conducted studies confirm the high efficiency of the proposed technology and guarantee increased strength and durability of geopolymer concrete.
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Fine-grained cement concrete with compressed structure, modified with basalt technogenic highly dispersed powder

https://doi.org/10.58224/2618-7183-2025-8-4-2
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Abstract
At present, improving the performance properties of concrete for dry and hot climates due to changing climatic conditions is of increasing interest to a wide range of researchers from the point of view of their practical application in the production of construction products. The paper investigates the possibility of synthesizing a spatially reinforced fine-crystalline structure of cement concrete for dry and hot climates, modified with basalt dust. The introduction of basalt dust waste into the composition of cement concrete forms the structure of artificial stone with the most dense packing. This is achieved by using a complex modifier based on basalt production dust removal waste together with a plasticizing additive in the composition of concrete for dry and hot climates. The introduction of these additives allows creating the best conditions for the process of forming the structure of cement stone from the standpoint of water content. Providing water content at all stages of the synthesis of modified stone allows for the acceleration and more complete flow of hydration and structure formation processes. The combined use of additives, as studies have shown, improves the performance properties of cement concrete, and therefore its use in the production of an expanded range of building products.
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Effects of multi-walled carbon nanotubes on polymer degradation in modified binder and their impact on the performance of stone mastic asphalt concrete

https://doi.org/10.58224/2618-7183-2025-8-4-3
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Abstract
Bitumen, the primary binder in asphalt concrete, lacks sufficient resistance to prolonged mechanical and environmental stress. To improve its durability, styrene-butadiene polymers are commonly used, although they are prone to oxidative degradation and phase instability. This study proposes a nanostructured approach to enhancing the stability and performance of polymer-modified bitumen (PMB) through the synergistic use of multiwalled carbon nanotubes (MWCNTs) and hydrocarbon plasticizers-specifically, selective oil refining extracts (SORE) and vacuum distillates (VD). Short-term oxidative degradation was assessed using isothermal RTFOT aging at 153, 163, and 173 °C. A classical first-order Arrhenius kinetic model was applied, with dynamic viscosity serving as a rheological proxy for SBS network integrity. Nanomodified compositions exhibited a 6-7-fold reduction in degradation rate constant (from 13.97 × 10⁻⁵ to 1.98 × 10⁻⁵ s⁻¹) and a 25-60% decrease in the preexponential factor, indicating suppressed molecular mobility and enhanced network cohesion. Performance was validated on SMA-16 specimens, showing up to 240% improvement in shear adhesion at 50 °C and 27% higher water resistance. Rutting resistance also increased, with rut depth reduced to 1.6–1.8 mm after 20,000 loading cycles. To integrate physical, mechanical, and durability characteristics, a set of Partial Quality Criteria (PQC) was developed and used to calculate a Generalized Effectiveness Coefficient (GEC), supporting multi-criteria optimization of asphalt mixtures. These findings confirm that nanostructured dispersed systems based on MWCNTs and hydrocarbon carriers not only delay oxidative degradation but also ensure multifunctional performance gains critical for high-traffic pavement applications.
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Influence of mechanical activation on the characteristics of glass concrete

https://doi.org/10.58224/2618-7183-2025-8-4-4
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Abstract
This work presents the study of effect of mechanical activation on the properties of glass concrete binder, based on mechanically activated glass and calcium oxide. The goal of the study was to identify patterns of changes in the microstructure and phase composition of the material with different durations of grinding and subsequent hydration.
We found that under mechanical activation for 12 minutes, all calcium oxide enters into a chemical reaction with the formation of the mineral combeyite (Na₂Ca₂Si₃O₉). Further hydration of the material leads to the transformation of combeyite into diverite (Na₂Ca₃Si₆O₁₆) and wollastonite (CaSiO₃). The microstructure is characterized by lamellar structures, an increase in strength is provided by a decrease in the particle size and an increase in the chemical interaction of the components.
It is shown that the duration of mechanical activation has a significant effect on the physical and mechanical characteristics of the material. A correlation was established between the duration of grinding and the strength and elastic modulus indices. Thermal and moisture treatment additionally increases the strength of the material, reaching values over 100 MPa.
The obtained results demonstrate the potential of the proposed technology for creating highly efficient building materials with specified physical and technical characteristics, contributing to the savings of traditional cement binders and reducing the pollution of the construction industry.
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Development of a modified bitumen emulsion to enhance the operational properties of asphalt concrete

https://doi.org/10.58224/2618-7183-2025-8-3-1
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Abstract
At present, the primary objective of the road construction industry is to increase the service life of road pavements by implementing innovative technologies that meet modern standards of operational reliability. The key advantages of bitumen emulsions were analyzed, including improved adhesion and cohesion, environmental safety, resistance to water exposure, rapid curing and opening to traffic, applicability under cold conditions, as well as enhanced stability and durability. The research findings confirm the benefits of using bitumen emulsions in road construction, contributing to high-quality and long-lasting pavement performance. Studies were conducted on the modification of petroleum bitumen. The additional incorporation of Kulantau vermiculite into the composition enhances and stabilizes adhesion across a wide range of ambient humidity and temperature conditions. The adhesion process can be regarded as the adsorption of bitumen emulsion on the surface of mineral aggregates. Adsorption occurs through intermolecular interactions, and adhesion is improved by strengthening these interactions, which is achieved by increasing the activity of the bitumen emulsion through the introduction of additives with active functional groups. It was found that incorporating secondary polyethylene and Kulantau vermiculite into asphalt concrete leads to a noticeable decrease in the air void content. This reduction enhances the material’s resistance to moisture and freeze-thaw cycles.
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Analysis of the influence of temperature loads on the stress-strain state of a pre-stressed cylindrical shell

https://doi.org/10.58224/2618-7183-2025-8-4-5
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Abstract
The progressiveness of the idea of prestressing consists, on the one hand, in the possibility to regulate the stress state in accordance with the peculiarity of the structure operation, and on the other hand, in the expansion of the economically advantageous range of application of high- and high-strength steels. Such strengthening is also relevant for cylindrical shells, the throughput or storage volumes of which are directly proportional to the operating pressure. The most effective type of prestressing in this case is considered to be winding on the shell body at an angle to the longitudinal axis or in the annular direction without tilting the high-strength profile. In this regard, in this work, a theoretical study of the influence of temperature loads on the stress state of the combined shell was carried out. As a result of the study, an analytical evaluation method was developed that takes into account the mechanical, geometric values of the wall and wrapping material, as well as the parameters of the prestress, taking into account temperature effects. The developed method also found that the established ring stresses in the shell wall increase with an increase in the temperature gradient, and the stresses in the wrapping decrease. At a temperature gradient of 70°C, the ring stresses increased by 1.8 times, and the stresses in the wrapping decreased by 1.3 times. At the same time, the change in operating temperature has a noticeable effect on the distribution of stresses in the wall of the shell and wrapping. Thus, calculations of a main pipeline pre-stressed with steel wire showed that at a temperature gradient of ΔΤ=30°C, the achieved level of prestressing can decrease by 10-12% compared to the initial one, and at ΔΤ=50°C, the pre-stressed wrapping does not affect the stress state of the shell wall. The obtained results of the study indicate that, taking into account the temperature loads on the structure, it is possible to adopt the necessary design parameters for further design of steel shells even more accurately.
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Comprehensive analysis of digital technology applications in construction site management

https://doi.org/10.58224/2618-7183-2025-8-2-1
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Abstract
This study examines the transformative impact of digital technologies on construction site management in the Russian Federation. Using a multi-method research approach incorporating content analysis, comparative assessment, systems analysis, and SWOT evaluation, the research investigates how Building Information Modeling (BIM), Internet of Things (IoT) architecture, cloud computing, and artificial intelligence applications reconfigure traditional construction processes. Findings demonstrate that smart construction sites implement informatization across four critical dimensions: personnel management, machinery administration, material resource coordination, and construction target optimization. Comparative analysis reveals significant advantages of technology-enhanced approaches over conventional methods, particularly in multi-location collaborative workflows, simulation modeling, construction process visualization, and remote monitoring capabilities. The SWOT analysis identifies initial capital investment requirements, specialized workforce development, and systems integration complexities as primary implementation challenges. The research concludes that smart construction sites represent an evolutionary progression in the construction industry, with implementation effectiveness directly correlating to organizational digital maturity, ultimately establishing unprecedented levels of construction production efficiency and operational safety.
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