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Investigation properties of waste from the chemical and metallurgical industries to assess the possibility of their use in concrete production

https://doi.org/10.58224/2618-7183-2025-8-4-7
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Abstract
The investigation was conducted on waste from the chemical industry in the form of carbide silt and metallurgical industry in the form of microsilica. For the study, X-ray phase analysis used on a Shimadzu XRD-7000 diffractometer in Cu Kα radiation. Electron microscopic studies were carried out according to GOST R ISO 22309-2015 on a Tescan Vega III SBH electron microscope with an integrated Oxford X-Act energy-dispersive microanalysis system. The Co standard (MAC, reg. no. 9941 Co) and a cassette of standard samples (MAC, reg. no. 11192) were used as samples. Samples were prepared at the Quorum Q150RES spraying station. The amount of raw sludge components was calculated taking into account the preservation of the saturation coefficient and modular characteristics of the cement plant. The calculation of the raw mix consisted in determining the ratios between its components based on the chemical composition of the raw materials and the specified characteristics of the clinker. The possibility is shown and the limits of carbide silt input are determined for use as a lime component of raw sludge in obtaining cement clinker. The possibility of adjusting the lime component of raw sludge by using microsilica is established, which will allow maintaining a balance in silicon content. The identity in the formation of the main clinker phases formed during sludge firing for the pilot sample and the sample made from the enterprise sludge is proven by the X-ray method. Cement of the CEM-II/A22.5N brand was obtained in laboratory conditions, the properties of which correspond to the properties of cement of the industrial enterprise. It is shown that the use of carbide silt and microsilica in the cement industry will allow not only to use them as raw materials, but also to improve the environmental situation in the territory adjacent to these enterprises.
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Influence of carbon black additives and finely ground waste from stone wool production on characteristics of cement systems

https://doi.org/10.58224/2618-7183-2025-8-4-8
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Abstract
The object of research is cement composites with additives of carbon black and finely ground waste stone wool production. The work aims to design a mix of a cement composite with the additives of carbon black and finely ground waste from stone wool production, which achieves the best strength characteristics. The results show that carbon black is represented on average by particles of 155 microns with inclusions of large agglomerates up to 1-2 mm in size, consisting of almost homogeneous nanoparticles 10-20 nm in size. Carbon black is distinguished by high hydrophobic properties with a true powder density of 900 kg/m3 and a bulk density of 300 kg/m3. The chemical composition of black carbon is 70-80% carbon and 10-15% oxygen, and it also contains impurity compounds of zinc, iron, sulfur, silicon, and other elements. Carbon additives acquire hydrophilic properties in the presence of a plasticizer, and the degree of their influence on hydration becomes less pronounced. The contraction of the binder during the first three hours of hardening is reduced when carbon black is introduced into the cement system in an amount of 8%. A composition with the best strength characteristics was obtained: the content of finely ground waste from stone wool production is 6% by weight of the binder; carbon black content is 4-5%; W/C = 0.2. However, there is difficulty in mixing the mixture at such a low W/C. With a water-cement ratio of 0.3, this problem is solved, and the strength characteristics remain quite high.
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Calendar planning of construction production, taking into account stochastic impacts

https://doi.org/10.58224/2618-7183-2025-8-4-9
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Abstract
The objective of this project is to enhance the technicues for creating informational models of alternative scenarios for the execution of the schedule and to expand the timeframe for predicting the progress of construction activities in the face of unpredictable factors. As a result of the study, the structure of a cellular automaton with memory, the cells of which quantitatively describe the states of objects of construction production, and the rules of transition between them were optimized. This paper introduces a comprehensive model framework for analyzing technologically and organizationally intertwined processes inherent in construction production. The model incorporates cellular automata to simulate spatial-temporal dynamics, vectors of complex resources to quantify heterogeneous inputs, and intricate process representations to capture the nuanced interdependencies within the cosnstruction system. A meticulously designed methodology has been developed to quantitatively evaluate technological and organizational capabilities, as well as the efficiency of implementing complex processes under constraints on both elemental and aggregated non-storage resources. This approach integrates advanced analytical techniques to assess performance metrics and identify optimization opportunities, ensuring alignment with strategic objectives and resource limitations. The proposed approach provides a robust analytical tool for optimizing construction workflows and enhancing overall project performance, leveraging advanced systems theory and resource optimization techniques.Methods for intensive and extensive optimization of complex process efficiency are formulated. Methods for optimal software implementation of the obtained algorithms are determined. In the shell of the relational database management system, a software package for forming basic and complex structures of a cellular automaton with memory is implemented.
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Planning, architectural, and construction solutions to create a comfortable environment for small cities near megacities

https://doi.org/10.58224/2618-7183-2025-8-4-10
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Abstract
Due to megacities’ rapid growth and modernization, new development opportunities are opening up for small cities near megacities, affecting their planning, architectural, and construction solutions. This often causes contradictions between the interests of developers, the population, and city authorities. Each party has interests that do not coincide with the values and priorities leading to complex situations affecting the city development. This article considers the urban development of Qosshy (Kazakhstan), focusing on the village’s transformation into a city of regional significance. The objective is to evaluate architectural and planning solutions in combination with socioeconomic opportunities for the development of Qosshy as part of the Astana agglomeration, according to the General Development Plan for Qosshy and the Comprehensive Development Plan for the Astana Agglomeration for 2024-2028. The study focuses on the distinctive features of Qosshy’s urban development, considering the influence of geographical, social, economic, political, and regional factors. The research methodology includes an analysis of documentation, literature, and the results of an online survey conducted by the authors. Qosshy’s residential development reflects regional characteristics, emphasizing creating comfortable living conditions while respecting the traditional lifestyle. Its architecture is shaped by elements of its historical development combined with modern and socially driven approaches. The authors propose practical measures aimed at gradually reconciling the interests of all stakeholders, which could effectively contribute to Qosshy’s development. This article will interest researchers and professionals in urban planning and architecture of small cities.
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Strengthening of monolithic concrete slabs against pushing

https://doi.org/10.58224/2618-7183-2025-8-2-4
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Abstract
Significant stress concentrations occur at the interface of floor slabs and columns in widely used monolithic reinforced concrete beamless frames. Therefore, the strength of the floor slabs must be checked for pushing under the loads from columns, bearing walls or stiffening diaphragms. The analysis of engineering solution of beamless monolithic reinforced concrete slabs of the administration nine-storey building with frame-walled load-bearing system is made. The strength thereof for pushing is found to be not provided under the given loads in a number of cases, due to this, experimental studies of strengthening the near-column areas of floor slabs have been carried out. When restoring the structures that suffered defects and damages in the course of their operation, composite materials having high tensile strength, low weight, constructibility and resistance to aggressive influence are widely used. The presented method for strengthening the near-column areas of floor slabs for ensuring their pushing strength with the use of chemical anchors has been developed, and a comparative analysis of the calculation results of the near-column areas of floor slabs with the adopted strengthening method with the results of experimental studies of slab fragments has been carried out. The operating conditions of the near-column areas of the floor slab have been simulated under the test method, and the results of the experimental samples testing are presented. All samples were found to have been destroyed by pushing through, with the destruction being of a plastic nature. The results of assessing the application of transverse reinforcement to the load-carrying capacity of the slab on pushing-through are presented. The results of experimental studies on assessing the pushing strength of extreme parts of monolithic floor slabs with columns reinforced with transverse glued-in reinforcement have shown good efficiency.
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Optimization of concrete composition with polypropylene fiber to improve their crack resistance in road construction conditions

https://doi.org/10.58224/2618-7183-2025-8-2-5
Abstract
The study included a detailed examination of the crack resistance of heavy concrete and foam concrete that were not subjected to autoclave curing. An important aspect of this study was the use of polypropylene fiber as a reinforcing material, which made it possible to identify differences in the characteristics between reinforced and unreinforced samples. The purpose of the work was to evaluate the mechanical properties of the materials under study, as well as their behavior during destruction. For this purpose, the criteria of fracture mechanics were used, which made it possible to establish not only the strength and deformation characteristics, but also the force and energy indicators of crack resistance. The experimental results showed that the addition of polypropylene fiber significantly improves the strength characteristics of both heavy concrete and foam concrete. This improvement was especially noticeable in the case of foam concrete, which, due to reinforcement, demonstrated increased crack resistance. This is due to the fact that polypropylene fiber promotes a more uniform distribution of stress in the material, which in turn reduces the likelihood of cracking and improves resistance to destruction. In addition, the study confirmed that the use of polypropylene fiber not only increases strength, but also improves the durability of concrete, making them more suitable for use in construction, especially in conditions where materials are subject to significant mechanical loads and adverse environmental factors.
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Features of the synthesis of construction geopolymer composites

https://doi.org/10.58224/2618-7183-2025-8-2-6
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Abstract
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. X-ray diffraction analysis of the obtained samples, as well as the results of scanning electron microscopy, electron dispersion spectrometry, differential-thermal analysis, ad infrared spectrometry confirm the presence in the geopolymer paste of products traditionally necessary for the hydration reaction: aqueous aluminosilicates, aluminates and silicates of sodium and calcium, quartz, calcite, feldspars similar to albite and orthoclase, micas, etc. 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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Methods to select structural solutions for wind power generators in low-rise development

https://doi.org/10.58224/2618-7183-2025-8-2-7
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Abstract
The article is devoted to the prospects for the development of renewable energy sources, in particular wind energy, in rural areas of the Rostov region (Russia). The analysis of the state program of the Russian Federation "Integrated Development of Rural Territories" was carried out. The primary measures that contribute to the implementation of directions for the development and improvement of the reliability of power supply through the use of wind energy are considered. The aim and objectives of the study are to create a classification and develop a methodology for selecting design solutions of wind turbines in low-rise residential construction, to develop criteria for evaluating the choice of renewable energy source (RES) technologies, to conduct a multi-criteria analysis of different types of wind turbine designs and to select the most optimal type of wind turbine design by applying multi-criteria analysis methods for selecting optimal wind turbine designs. The possibility of applying the method of multi-criteria analysis for the choice of design solutions for WPPs is substantiated. The assessment of the Rostov region territory and its priority for the placement of wind farms was demonstrated. The classification of wind turbines has been carried out. Design solutions for wing generator are presented. A technique for choosing optimality criteria is formulated. The results of studies by different scientists are summarized and compared with the proposed methods To select the optimal design of the wind turbine, a multi-criteria decision analysis was applied. Methodology for selecting wind energy generation technology elaborated in the course of research by applying multi-criteria analysis, allows us determining with the highest accuracy the most efficient and economically viable design of the wind power plant.
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Photocatalytic self-cleaning lime coatings

https://doi.org/10.58224/2618-7183-2025-8-2-8
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Abstract
The article presents the results of assessing the self-cleaning properties of lime coatings. The use of zinc oxide immobilized on synthesized aluminosilicates as a photocatalyst is considered. The technology of synthesis and properties of aluminosilicates are described. The photocatalytic activity of zinc oxide is analyzed depending on the technology of obtaining the photocatalyst. It was found that the band gap width of the photocatalyst obtained by immobilizing zinc oxide on synthetic zeolite decreased from 3.37 eV to 2.7 eV. Comparison of the self-cleaning ability of lime coating samples, in the formulation of which the photocatalyst was introduced, is carried out using the methods specified in the regulatory documentation- according to the test method in accordance with GOST R 57255-2016, according to the method of the Italian standard UNI 11259. The results of tests according to the methods established in regulatory documents indicate the high photocatalytic activity of the lime coating. It has been established that the lime coating with the use of zinc oxide photocatalyst immobilized on synthetic zeolite exhibits high photocatalytic activity. In accordance with the requirements of the Italian standard UNI 11259, the photocatalytic activity of the surface after 4 hours is R=21.94-55.42%, and after 26 hours – 51.96 - 98.2% depending on the specific surface of zinc oxide.
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Active-adaptive construction project management system based on self-organizing maps for optimization of architectural and structural solutions

https://doi.org/10.58224/2618-7183-2025-8-2-9
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Abstract
This research focuses on developing and implementing an active-adaptive construction project management system based on Kohonen Self-Organizing Maps (SOM) technology. The high variability of architectural and structural solutions, complex design dynamics, and multifactorial engineering calculations in modern construction necessitate creating flexible automated management systems capable of self-regulation. The research methodology integrates cluster analysis of design characteristics, multidimensional topological mapping of structural elements, and neural network analysis using SOM algorithms. The empirical base encompasses data from 38 construction projects of various scales during 2019-2023, with a total area exceeding 4.3 million square meters. Results demonstrate a 36.4% reduction in design documentation development time, 21.7% decrease in structural material consumption, and 17.3% improvement in building energy efficiency. A strong correlation (r=0.83) was established between the degree of structural solution optimization and economic efficiency of construction projects. The developed system provides dynamic visualization of multi-parameter design solution structures, enabling real-time identification of critical contradictions and preventive correction of potentially problematic structural nodes. The research significance is confirmed by multifactorial economic implementation efficiency (ROI=2.7) and substantial reduction in construction timeframes (average 14.6%).
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