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Ключевые слова: water absorption

The production technology of high-performance ceramic stones based on the products of processing of coal dumps

https://doi.org/10.58224/2618-7183-2024-7-4-4
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Аннотация
The aim of the research was to study the main properties of coal dumps processing products, their impact on the quality of finished products and the development of a technology for manufacturing process of ceramic stones with high efficiency. Structural features and chemical-mineralogical composition of coal dumps processing products have been studied, their pre-fired and firing ceramic properties have been studied. The raw mass compositions were chosen based on this, along with testing of laboratory samples. The impact of different technological factors on the properties of the final products has been identified and established. The material composition and technological properties of fine, fine and medium fraction materials are shown. A basic classification of the products derived from processing of waste heaps has been conducted based on grain composition, coal component content, and mineralogical and petrographic characteristics. The optimal formulations for raw material mixtures and the manufacturing process for producing large ceramic bricks with an average density below 800 kg/m3 are described. The impact of grinding degree of the waste heap processing products and the firing temperature on the strength of the samples have been established. The incorporation of finely dispersed products from waste heap processing decreases the density and strength of the samples. It is suggested to use semi-rigid extrusion technology for molding these products. Utilizing processed coal waste materials in wall ceramics production will aid in their disposal and enhance the environmental conditions in the area. This research was conducted in Russia at Don State Technical University in Rostov-on-Don. In creating a technology for producing ceramic blocks from screenings of waste heap processing in Eastern Donbass, minimal production costs and high profitability of production are envisaged.
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Influence of corn cob ash additive on the structure and properties of cement concrete

https://doi.org/10.58224/2618-7183-2024-7-3-2
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Аннотация
In accordance with the Sustainable Development Goals (SDGs) concept, there is a need to find technologies that would help make concrete production less energy intensive and more environmentally friendly. One technology involves substituting some mineral components in concrete with rapidly renewable plant-based alternatives. This study aims to establish the essential patterns among the concrete composition, micro-structure, and properties of cementitious composites modified with corn waste. Additionally, it seeks to explore the potential for producing high-quality composites using this waste material. To assess the effectiveness of this kind of waste, the strength of the cement-sand mortar, several characteristics like compressive strength, flexural durability and water absorption of hardened concrete were studied. It is established that introducing corn cob ash (CCA) to substitute a part of the cement up to 16% is justified and allows to obtain mortar and concrete with enhanced properties. CCA has a beneficial impact on the properties of Cement Sand Mortar (CSM) when replacing cement by no more than 15%. The maximum effect was achieved at 10% CCA, and the rise of compressive and flexural strength were 6.06% and 6.32%. In concrete with a CCA amount of 8%, the most impressive growth of compressive strength was 7.14%, and the lowest value of water absorption, which is 10.31% lower compared to the ordinary composition. Including CCA reduces the properties like workability, density of concrete mixtures, and the hardened composite density. The scientific results obtained prove the possibility of using CCA as an effective mineral pozzolanic additive that improves the properties of concrete.
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Properties of Verkhnealkunsky deposit mudstones used as raw materials to manufacture clinker tiles

https://doi.org/10.58224/2618-7183-2024-7-3-7
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Аннотация
The article writes about the development of mudstone-based raw material compositions used to manufacture clinker tiles with improved physical and technical properties. Clinker tiles are one of the popular roofing materials. Compared to other roofing covering options, clinker tiles have higher strength, more resistance to aggressive environments, and better aesthetic characteristics. Clinker tile production is relevant due to the fact that currently architects and building constructors are showing great interest in such an elite roofing material, but due to the economic situation, this roofing material is no longer imported to Russia, with an empty market niche having been formed. Many Russian brick factories are planning to install additional technological lines to manufacture ceramic tiles, but the current demand is to produce clinker tiles. The main unresolved issue concerns raw materials since traditional raw materials – loams and clays – are very rarely suitable for the production of low-temperature sintering clinker tiles. Having studied a large amount of academic literature and carried out the necessary laboratory studies, the authors of this article, under the guidance of the Chair of the Construction Materials Department, Prof. V.D. Kotlyar, pay serious attention to such raw materials as mudstones from the Verkhnealkunsky deposit of the Russian Republic of Ingushetia. The article provides a general description of mudstones, including their chemical and mineral composition as well as their structural features for the production of clinker tiles. It has been experimentally established that the degree of their grinding has a significant influence on technological properties of both mudstones and the end products. Based on raw material mixtures with a grain composition of 0-0.16 and 0-0.08 mm, it is possible to manufacture clinker tiles using the extrusion molding method without introducing corrective additives. The data obtained will make it possible to develop technological regulations to manufacture clinker tiles based on Verkhnealkunsky deposit mudstones.
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PERFORMANCES OF HIGH POROUS CELLULAR CONCRETE

https://doi.org/10.34031/2618-7183-2020-3-5-5-14
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 5-14 стр.
Аннотация
The widespread use of cellular concrete for enclosing structures forces researchers to develop ways to improve their performance and durability. Compositions of aerated and foam concrete with the use of waste heat power engineering have been developed. The optimal formulation ratios have been identified that contribute to the creation of a rigid interpore matrix and water-repellent pore protection. The regularities of the synthesis of aerated concrete and foam concrete were established, which consist in optimizing the processes of structure formation through the use of a polymineral cement-ash binder and a pore-forming agent. The mix composition intensifies the process of hydration of the system, which leads to the synthesis of a polymineral highly porous heterodispersed matrix. The increased activity and granulometry of aluminosilicates predetermine an increase in the number of contacts and mechanical adhesion between particles during compaction, strengthening the framework of the interpore partitions. The mechanism of the influence of the composition of the concrete mix on the microstructure of the composite is established. The calculated sound insulation of airborne noise shows sufficient characteristics for using aerated concrete blocks as enclosing structures. One of the main advantages of aerated concrete is its low thermal conductivity, which is especially important from the point of view of ensuring the energy efficiency of buildings and structures. Even in spite of the high values of open porosity of the developed aerated concrete, the rigid frame makes it possible to achieve almost 2 times higher frost resistance characteristics than that of the reference specimen.
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