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Vol. 8 Issue 6

Archives Journal Construction Materials and Products Vol. 8 Issue 6

Research on air purification from pulverized large-tonnage tailings of non-ferrous metal ores and the possibility of their use as secondary raw materials

https://doi.org/10.58224/2618-7183-2025-8-6-1
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Abstract
Pulverized waste (large-tonnage tailings) from the enrichment of non-ferrous metal ores pose a significant environmental threat and a health hazard to the personnel of enterprises and the population of nearby territories. In this regard, this study is devoted to solving the problem of dust suppression with the prospect of subsequent complex tailings processing. The effectiveness of a combined method combining fine-dispersed hydraulic spraying and pulsating ventilation for dust deposition from the tailings of the former Kentau Enrichment Plant (Kentau, Kazakhstan) has been experimentally studied. Laboratory tests were carried out on a specialized stand with monitoring of microclimatic parameters. The results showed that the combined method reduces the dust deposition time by approximately 30% compared to traditional irrigation and by more than two times compared to natural precipitation. Optimal process parameters have been established: nozzle diameter of 10 microns, liquid pressure of 5.4 MPa, air flow velocity of 4 m/s, pulsation frequency of 13 Hz. Based on the X-ray phase analysis of the tailings composition (the total content of zinc compounds is ~3.77%, lead ~4.47%), the economic feasibility of their complex processing is substantiated. A two-stage technology is proposed: preliminary, associated extraction of valuable metals (Zn and Pb) followed by the use of a non-metallized residue rich in oxides of silicon, aluminum and calcium in the production of building materials (cement clinker, ceramics). Thus, effective dust suppression is the first step towards the transition from passive waste storage to active recycling within the framework of the principles of circular economy, which will significantly improve the environmental situation in the region.
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Improving the performance of concrete for bridge structures

https://doi.org/10.58224/2618-7183-2025-8-6-2
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Abstract
Concrete for ambitious engineering projects, including bridges, must meet certain requirements related to strength, water resistance, frost resistance and plasticity. The objective of the article is to improve the efficiency of concrete for bridge structures. The compositions of high-strength building composites have been optimized with a reduction in the proportion of the clinker component. The densest packing of filler particles has been achieved, providing a self-compacting effect during hardening. The compositions of building composites have been optimized at the macro-, micro- and nanolevels to obtain a high-density matrix packing and increase the strength of the composite (including taking into account the granulometric analysis of fillers and the choice of superplasticizer). New properties of high-strength building composites (rheology of highly concentrated dispersed systems, shrinkage deformations, workability, setting time, etc.) have been studied. The results of fresh properties of the developed mixtures showed their compliance with the P5 grade, which indicates that they have good transportability to the place of manufacture of bridge structures. The study of the physical and mechanical characteristics of cement composites (average density, porosity, compressive and bending strength, elastic modulus, frost resistance, shrinkage, Poisson's ratio) showed that the obtained materials can be effectively used for the construction of critical structures, including bridges.
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Improving the operational characteristics of wall ceramic products through the use of coal waste heap processing materials

https://doi.org/10.58224/2618-7183-2025-8-6-3
Abstract
Existing methods for disposing of coal industry waste do not ensure their effective use in the production of building materials, leading to the accumulation of waste dumps and worsening environmental conditions. This research addresses the performance limitations of traditional ceramics by proposing the integration of fine-grained coal mining waste as a primary raw material component. This strategy serves a dual purpose: resolving waste disposal concerns and enhancing ceramic properties through structural modification. The study evaluates the key physicochemical properties of such waste and their effect on material quality. It was determined that the inclusion of fine waste fractions necessitates optimized firing parameters to counteract reductions in density and strength. Empirical models defined the relationship between waste fineness, sintering temperature, and mechanical properties. A specialized semi-dry pressing method was engineered to minimize strength degradation and ensure the production of consistent ceramic blocks. The overarching goal of this technological approach is to achieve cost reduction and heightened product reliability via an optimized synthesis of raw materials and thermal regimes. Application of this method using Eastern Donbass coal waste is envisaged to ensure economic viability while upgrading the technical profile of the resulting construction materials.
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Adhesive bond integration into steel structures of emergency shelters

https://doi.org/10.58224/2618-7183-2025-8-6-4
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Abstract
Natural hazards and resulting technological disasters are currently becoming regular. In these conditions, the creation of emergency shelters is a foremost task of the government to provide the harmed population with housing units in a short time. In the framework of the integration of advanced materials and technologies into steel structures to create safe emergency shelters, experimental research is conducted into adhesively bonded steel-to-steel connections based on epoxy resin laminate. Such connections are interesting for prefabricated modular construction of emergency shelters, as they allow avoiding sectional weakening and stress concentrators common to welding and screw connections. Young’s modulus and shear modulus determined for the epoxy adhesive, are crucial parameters for accurate design. The paper studies the strain distribution in epoxy bonded steel-to-steel connections, identifies strain stages and strain concentration zones, leading to a combined cohesive-adhesive fracture. The obtained results can be used to transfer form empirical building to theoretically substantiated strength analysis of safe and reliable assemblies of prefabricated adhesively bonded steel structures.
The paper presents integrated experimental research into epoxy bonded steel-to-steel connections based on FibArm Resin Laminate+. Tensile strain distribution is identified along the sample longitudinal axis. Four strain stages (elastic, yield plateau, plastic and pre-fracture) are determined together with the evolution of localized elastoplastic strain regions on the surface of the steel plate.
Identified are a nonuniform strain distribution with alternating compressive and tensile strain regions that correlates with transitions on strain-stress curves. The maximum primary relative strain in the epoxy adhesive reaches 3.38 % and concentrates along the adhesive–steel interface
In accordance with GOST 25717-83 requirements, the shear modulus of 236 MPa and Young’s modulus are determined for the epoxy adhesive by B method and the t distribution with the confidence level of 5%. These parameters are used for a transition from empirical building to theoretically substantiated finite element analysis of the stress-strain state of the steel-to-steel connection.
The obtained results help to optimize the design of epoxy bonded steel-to-steel connections in engineering, promoting more continuous load, reduced weight and defects as compared to conventional techniques (welding and screw connections). This work confirms the efficiency of sanding of the steel surface in gaining the best adhesion and resistance to environmental impacts, which is relevant for the iron, aerospace and construction industries.
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Numerical investigation of the dynamic impact of hybrid basalt fibre on the damage and split way resistance of reinforced concrete aerodrome pavement

https://doi.org/10.58224/2618-7183-2025-8-6-5
Abstract
The study used Finite Element Analysis (FEA) to examine the influence of aircraft landing loads on the crack resistance of hybrid basalt fibre-reinforced aerodrome pavements. The study replicated a load from an Airbus A321neo on 25 distinct concrete mixtures, each incorporating different proportions of basalt micro and macro fibres. We measured the total deformation of each mix after 7, 14, and 28 days of curing. The results showed that all of the fibre-reinforced mixes had a significant and consistent decrease in deformation compared to the unreinforced control mix. Mix M11, which had 2% Basalt Microfibre and 1% Basalt Macro Fibre, was found to be the best mix. This particular hybrid combination consistently exhibited the lowest total deformation values throughout all three curing periods. For example, after 28 days, the control mix had a deformation of 0.0058265 mm, while Mix M11's deformation was only 0.0057363 mm. This numerical evidence shows that hybrid fibre reinforcement works together to make aerodrome concrete stronger and able to hold more weight. The results indicate that enhancing the hybrid basalt fibre content is an effective approach for creating pavements that are more resilient, long-lasting, and environmentally friendly, which is essential for enhancing safety and operational efficiency in the aviation sector.
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Heat and mass transfer in concrete mixtures during transportaion along the route «Manufacturer of liquid – phase solution – consumer of solid-phase concrete»

https://doi.org/10.58224/2618-7183-2025-8-6-6
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Abstract
The durability of concrete is a critical operational parameter that directly determines the service life of concrete structures. Achieving a concrete mixture with specified rheological and strength properties is a vital technological stage, as the quality of the initial material governs the load-bearing capacity of the final reinforced concrete elements. In the technological process, the transformation of concrete mixture components into a liquid non-Newtonian system with distinct rheological characteristics, followed by solidification into a structured composition, depends significantly on the variability of physico-mechanical, thermophysical, and structural-mechanical properties of both individual components and the overall mixture.
Developing comprehensive mathematical models that describe the entire technological cycle—from production to placement—poses a multifactorial challenge aimed at ensuring the design durability of construction structures. Particular emphasis is placed on modeling heat and mass transfer processes within heterogeneous concrete systems, as these non-stationary external influences critically affect the operational characteristics of the final material. Transport and hardening parameters heavily influence structural transformations within the cement stone, ultimately impacting strength and deformation properties. Effective resolution of this problem necessitates modern numerical modeling techniques that incorporate the rheological behavior of concrete mixtures and hydration kinetics.
The proposed mathematical and algorithmic framework underpins efforts to minimize concrete structure degradation by simulating rheological parameters during transportation and placement. A principal achievement is the creation of heat and mass transfer analysis algorithms that integrate predictive models with real-time monitoring data, laying a methodological foundation for future technological process control systems. The solutions further include optimization of logistical parameters under varying temperature and humidity conditions and the establishment of criteria to assess the structural homogeneity of concrete mixtures.
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Kinetics of contact formation between dissimilar crystalline materials during the period of active strain of the first stage of a solid-phase topochemical reaction

https://doi.org/10.58224/2618-7183-2025-8-6-7
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Abstract
One of the key processes that largely determines the quality of a permanent precision joint formed in the solid state under pressure and heat, which belongs to the class of solid-state topochemical reactions and proceeds in three main stages, is the formation of actual contact, which transitions to a state of physical contact (stage one) at a certain ratio of the level of thermal strain and the contact area. The latter is formed due to plastic strain and the shape change of microprotrusions on the surfaces being joined, which alters the mechanical properties of the resulting contact pads and the near-contact volume of the metal microprotrusions. To develop valid process parameters for producing a high-quality joint, it is important to establish the influence of temperature, pressure, and the height of microroughness of the contacting surfaces of the materials being joined on the kinetics of individual stages of the solid-state topochemical reaction under thermal strain. This paper presents the kinetic dependencies of contact formation during the period of active strain or active loading between dissimilar crystalline materials using the example of synthetic single-crystal corundum – MB copper (oxygen-free) and provides their physical and mathematical justification. Knowledge of the kinetic laws governing the formation of actual contact and the transition to physical contact at a certain ratio of the level of thermal strain action and stress state (the ratio of normal and tangential microstresses of the 2nd kind on the surface of contact pads and in the volume of microprotrusions) and the occurring mechano-physical-chemical processes on the surface of the forming contact pads and in the volume of microprotrusions, allows for a more rational consideration, construction and implementation of the technological process for obtaining a precision detachable (contact of the traction sheave with the cable) or permanent connection of materials in a wide variety of combinations, including those with different nature of chemical bonds and resistance to plastic strain, and will also allow for the consideration and assessment of the role of microstresses of the 2nd kind in the occurrence and propagation of microcracks in the grain of the metal and the provision of recommendations for the prevention of sudden brittle failure of welded building metal structures.
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Environmental safety management of city life cycle through low-carbon principles

https://doi.org/10.58224/2618-7183-2025-8-6-8
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Abstract
The contemporary urban environment, being a complex system saturated with construction objects interconnected by engineering and social communications, contains numerous potential sources of hazardous technosphere situations. Preventing and mitigating their consequences becomes feasible only through timely automated monitoring of early warning signs and forecasting dynamics of development. At the same time, construction objects within the urban context consume significant material and energy resources, contributing to increased carbon emissions impacting the environment. Therefore, there is a pressing need for digital instruments capable of managing these processes across their entire lifecycle. In this regard, effective means of ensuring ecological safety in cities involves monitoring technical, organizational, and functional components of works conducted and planned for both construction and maintenance phases of urban infrastructure. Based on these measures, maintaining the carbon sustainability of urban immovable property and infrastructure funds becomes achievable when implemented within an adaptable City Information Model (CIM) tailored specifically for managerial tasks. The scientific novelty of the proposed research lies in developing scientific-methodological foundations for digital monitoring of current conditions and predicting the evolution of carbon state and resilience of constructed and operational urban objects and infrastructure integrated into a unified CIM. This approach serves as the basis for instrumentation aimed at managing ecological safety of construction objects. In the research, the technology of information modeling of city objects is constructed based on the author's factor space, incorporating monitoring and forecasting of conditions for realization and assessment of carbon sustainability of constructed and operated objects. This effort utilizes international databases regarding the carbon impact of construction materials and processes, along with analytical data derived from project estimates documentation of urban objects. Automated expert activity tools, including the integration of unmanned aviation systems, are utilized extensively. Algorithms for automated evaluation and forecasting of City carbon impact Indicator (CCII) are presented and to be used as a basepoint for unmanned city carbon analysis within city life cycle management. These algorithms aim to optimize recommended construction, restoration, or operational measures by leveraging results from drone surveillance, neural network detection, mapping, quantitative assessments, and dynamic parameter changes of objects. Ultimately, this allows for synthesizing optimal management decisions ensuring environmentally safe urban spaces towards the carbon homeostasis as an ultimate goal for modern city ecological management.
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Variatropic concrete compressive strength prediction under freeze-thaw conditions using machine learning methods

https://doi.org/10.58224/2618-7183-2025-8-6-10
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Abstract
The introduction of intelligent models, in particular using machine learning methods, opens up prospects for the development of the construction industry. The construction of regression models for predicting the physical and mechanical properties of various types of building materials is a promising and relevant area. The use of such models makes it possible to take into account complex and multifactorial dependencies, while minimizing the influence of the human factor. In the present study, variatropic concrete B30, obtained by centrifugation, acts as the test material. The dataset (351 objects) was assembled during laboratory studies to study the effect of freeze-thaw cycles on the strength characteristics of the material. Using the computer vision method based on the convolutional neural network U-Net, the damage on each of the concrete layers was assessed on different cycles. 4 machine learning models for predicting compressive strength were trained and tested on the collected dataset: Ridge Regression (RR), Random Forest (RF), CatBoost (CB) and Multi-layer Perceptron (MLP). The hyperparameters of the models were optimized using Grid Search + 3-fold cross-validation. As a result of testing the algorithms on a test sample, the best quality metrics were demonstrated by tree architectures: MAE for RF and CB 0.09 and 0.17 MPa, respectively, R2 = 0.99. The results are supplemented by SHAP analysis. The results obtained are a useful tool for optimizing the composition of variatropic concretes used under aggressive conditions.
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Plasma electrolyte discharge in metal powder production processes

https://doi.org/10.58224/2618-7183-2025-8-6-11
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Abstract
Zinc ultrafine powder has found applications in the medical, electronic, chemical, construction, and metallurgical industries. Existing methods of producing zinc powder have a number of drawbacks: some of them are highly energy-consuming, while others are characterized by low productivity and a coarse-grained structure of the powders. A solution to this problem can be found in the use of a gas discharge between an electrolytic anode and a metallic cathode immersed in an alkaline solution.The aim of this work was to study the combustion processes of a gas discharge between an electrolytic anode and a metallic cathode immersed in an aqueous solution of sodium hydroxide. The possibility of applying a gas discharge with a liquid electrolytic anode for the production of zinc powder from alkaline solutions has been established.The pulsed mode can be used at the voltages of the I-V characteristic curve only in the region where intensive hydrodynamic disturbances are observed and where a gradual increase occurs in the area of the metallic electrode surface covered by the gas discharge (U = 150–215 V for a 1% solution, U = 100–125 V for a 3% solution, and U = 70–110 V for a 5% aqueous solution of sodium hydroxide).
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