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Klyuev S.V.

Doctor of Engineering Sciences (Advanced Doctor), Associate Professor, Belgorod State Technological University named after V.G. Shukhov, Russia

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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Sustainable gypsum composites reinforced with basalt technogenic nanofiber

https://doi.org/10.58224/2618-7183-2025-8-2-2
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Abstract
Sustainable composites based on gypsum man-made stone are produced using a technology that excludes the firing stage. It meets the requirements for resource and energy conservation, does not harm the environment and can be used in the production of a number of biopositive building materials. The use of pure dihydrate gypsum from gypsum mold waste in the composition of sustainable gypsum composites predetermines the expansion of the scope of application of materials and products based on it. These wastes are characterized by stable physicochemical and mechanical properties. However, the features of the mineralogical composition require high costs for their use in the production of fired gypsum binders using classical technologies. Binders based on them have low strength and other physical indicators. Application without firing technology allows for the maximum use of all the unique properties of gypsum – creation of a comfortable environment, high resistance in fire conditions, good insulating characteristics, etc. By introducing highly dispersed basalt dust particles into the composition of stable gypsum composites based on dihydrate gypsum, gypsum stone is reinforced and compacted at the micro- and nanoscale levels. This is facilitated by the optimal values of the pressing force and humidity of the raw mix selected during the study. They are important technological parameters. The resulting high-strength gypsum composite is characterized by a fine-crystalline structure with higher performance indicators than conventional gypsum materials due to the screening of the moisture effect on it.
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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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Application of ash and slag waste from coal combustion in the construction of the earth bed of roads

https://doi.org/10.58224/2618-7183-2024-7-6-3
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Abstract
More than 1.5 billion tonnes of ash and slag waste from thermal power plants have been accumulated in the RF. The most promising direction of reuse is construction and repair of roads. The most material-intensive direction is the construction of earth bed. The aim of the study is to expand the practice of using ash and slag mixtures from thermal power plants for the construction of roadbeds in continental and polar climate. In order to achieve the goal set in the work the ash and slag mixture from different ash dumps of Irkutsk region was sampled. Ash and slag wastes can be considered as technogenic soils and classified according to GOST 25100 as gravelly sands and dusty sands. Ash and slag mixtures do not possess cohesion, have low values of internal friction angle, high porosity of particles and low specific weight, and small frost heave deformation. To evaluate the efficiency of ash and slag mixtures application in the structures of the roadbed of roads the design and construction of the roadway and the roadbed on the section of the road in the Irkutsk region was carried out. The technology of works on construction of earth bed layers from ash and slag mixtures is similar to the technology of erection of layers from soils. The constructed construction of road with earth bed from ash and slag mixtures has operational characteristics not lower than the construction of the adjacent road section with earth bed from local soils. Ash and slag mixtures can be used for construction of earth bed layers practically without restrictions.
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Design of steel fiber-reinforced concrete for slip forming

https://doi.org/10.58224/2618-7183-2024-7-5-2
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Abstract
Introduction. Slip forming is one of the effective and promising methods of concrete mix casting. Development of slip forming technologies largely depends on accumulated experience and tools, one of which is the composition design methodology. The use of special types of concrete, such as fiber-reinforced concrete, requires additional knowledge and the creation of special technological tools. The purpose of the study: to develop a methodology for designing steel fiber-reinforced concrete composition for slip forming. Methods and materials. Known methods for designing concrete and steel fiber-reinforced concrete compositions are used. A methodology for designing steel fiber-reinforced concrete composition for slip forming has been developed, consisting of two stages: designing the matrix composition to ensure a given ultimate extensibility of the mixture; designing steel fiber-reinforced concrete based on a pre-obtained matrix composition. Cement CEM I 42.5N, medium-sized sand, crushed stone with particles size 5-10 mm and 36 mm length steel milling fiber are used. Results and discussion. According to the proposed methodology, the composition of steel fiber-reinforced concrete with specified properties was designed (ultimate extensibility not less than 100 mm/m; cone slump 1...4 cm; compressive strength not less than 40 MPa; flexural strength not less than 6.5 MPa). The results of laboratory tests of the obtained composition are presented. In terms of strength, workability and ultimate extensibility, the composition meets the technical specifications. Conclusions. The proposed methodology of designing the composition of steel fiber-reinforced concrete for slip forming has been successfully tested in laboratory and can be recommended for use in production.
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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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Improving Reinforced Concrete Column Strengthening Techniques for Reconstruction Projects Using Composite Jacketing Formworks

https://doi.org/10.58224/2618-7183-2023-6-5-1
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Abstract
The paper looks at the issues of reconstruction of modern construction systems, in particular, the possibility of their functional repurposing. Examples from the global practice are provided to illustrate the conversion of industrial facilities for use as residential and public buildings. Based on an overview of scientific publications, the paper offers a set of rationales for the preservation of industrial facilities and highlights the benefits of reconstruction aimed at improving their residual lifespan and ensuring further reliable operation. Reconstruction is noted to enable resource savings, which allows efficiently investing in the development of modern machinery and technology as well as launching production of innovative products. Interior details are displayed as an example of industrial building conversion into a preschool educational facility.
The purpose of the study is to improve the techniques of enhancing the bearing capacity of reinforced concrete columns by using composite materials and reducing related labor inputs. To this end, it is suggested that removable or permanent formwork systems be replaced with a jacketing formwork combining the benefits of both removable formworks (quick turnaround, adaptability due to the use of high-strength and light-weight composites) and stay-in-place formworks (the factory-made decking forms part of the column to be reinforced and does not require extra finishing). The paper argues that a jacketing formwork is multifunctional, as it performs the protective function in addition to the molding one, and provides the description and schematic design featuring two formwork options. The use of jacketing formworks allows reducing labor inputs when reinforcing columns and restoring their geometric dimensions, thus cutting down on the overall reconstruction time.
A conclusion is made that the use of modern composite materials for manufacturing jacketing formworks allows not only making or reinforcing rectangular-section columns, but also changing the geometric configuration of the cross section for reconstruction purposes.
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