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In the article, the influence of the aluminosilicate part of fuel bottom ash and slag mixtures on the water demand of gypsum raw materials of dry building mixtures is considered. It is shown that the aluminosilicate filler has a plasticizing effect. This is due to the presence of microspheres in the composition of the filler. They reduce the amount of water needed to achieve normal gypsum paste consistency. This is reflected in other physical, mechanical and structural characteristics of gypsum. The ash filler in the optimal ratio with the gypsum binder compacts the structure of the stone. does not participate in chemical transformations. To increase the efficiency of the ash filler, it is necessary to introduce additional components that activate the processes of structure formation in ash-gypsum binders.

The publication is devoted to the study of the possibility of using ash and slag waste from hydraulic removal of fuel power plants in the production of building gypsum materials. These wastes are not used in industrial production due to the heterogeneity of composition and properties. This is a big and unresolved problem for many thermal power plants. However, when separating individual parts - carbon, aluminosilicate or magnetite - the possibility of using the selected part of the component increases. The paper considers the use of carbon and aluminosilicate parts as an additive in the composition of gypsum compositions. A comparative analysis of the properties of gypsum compositions modified with carbon and aluminosilicate additives is given. A higher efficiency of using a carbon additive for lightweight gypsum compositions has been established. The comparison was carried out in terms of compressive strength and average density. Additives were introduced in the amount of up to 30%. The ratio of tensile strength and density for modified mixtures was characterized by specific strength. It was higher for mixtures with a carbon additive. The introduction of porous mineral fillers - perlite and vermiculite - in a volume of up to 20% contributed to an even greater decrease in density. The best result was shown by mixtures with the carbon component of ash and slag mixtures and the addition of perlite. They can be used for green building.

It is known that the increasing demand for cement production is linked to the increasing world population, and the rapid development of construction technology. As a result of these factors, cement plants are causing a massive environmental problem by emitting CO2 into the atmosphere. This significant air pollution may contribute to global warming. The search for alternative eco-friendly materials is an urgent need. Fly ash is a by-product in the form of powder produced by burning pulverised coal in power plants in huge quantities. Having no useful application, it is an organic waste, causing problems in landfilling. It is a pozzolanic material high in alumina and silica, which in the presence of water, acquires the cementitious properties of a renewable secondary cement-based material. When it is added to different types of binder, a new type of binder can be formed due to the mutual influence of fly ash on the nature and speed of the processes. The aim of the study was to develop a composition based on fly ash with a high content of free calcium oxide to replace cement with an alternative binder in the production of structural materials. For this, it was made a series of composite samples of different properties to obtain multilevel reinforcement. These samples showed high compressive strength (up to 90 MPa), indicating the synergistic effect of the composite components and their proper selection in building structures. [ABSTRACT FROM AUTHOR]

The article presents a model of non-hydration hardening of dispersed systems - mineral binders (without the stage of hydration) and the results of studies of gypsum stone with ash filler from the standpoint of the formation of the optimal structure of the material of non-hydration hardening, as well as its density and strength. The model assumes the use of binary mixtures of dispersed components with different dispersions. The study was based on data on the granulometric composition and dispersion of gypsum powders and aluminosilicate microspheres. It was isolated from the ash-slag mixture - waste from a thermal power plant. The aluminosilicate microsphere contains not only microsized spherical particles of the amorphous phase but also nanosized grains in a sufficient amount. This makes it possible to control the particle packing density. Experimental verification of the optimization of the granulometric composition of a binary dispersed system based on gypsum and ash microspheres was carried out. Based on the results, the optimal content of the filler in the composition of the non-hydration hardening structure was established. It is shown that filling with highly dispersed particles affects the performance properties of the resulting modified stone. [ABSTRACT FROM AUTHOR]

The possibility of using glass hollow microspheres in self-reinforced gypsum composites in the work is investigated. The need to use microspheres for gypsum products is dictated by modern high requirements for safety and environmental protection to construction sites and the building materials industry. The dispersion characteristics and grain composition of Russian production glass hollow microspheres, as well as the main component, a gypsum binder, were studied. It was established that all compositions contain particles of micro- and nanometer size. It is shown that glass microspheres provide the structure of a composite with a hardened matrix a low density while maintaining the necessary strength without the introduction of expensive and environmentally unsafe chemical additives.

Waste disposal in the production of building materials and the organization of waste-free technological processes require a large amount of multilateral research. The application of basalt dust in the production of gypsum materials has been little studied. The paper investigated the effect of basalt dust - waste production of basalt fibers, on the working mixtures and the properties of hemihydrate of calcium sulfate paste (standard consistency, setting time of gypsum dough, water absorption of the resulting gypsum stone). It is known that the addition of basalt waste has a positive effect on strength, but there is no data on its effect on the rheological properties of gypsum mixtures. It was revealed that the introduction of basalt dust into the composition of the gypsum composite contributes to the change of the plaster mix rheology and of the properties of the gypsum structure. This must be taken into account when selecting optimized formulations of working mixtures on the hemihydrate of calcium sulfate.

Modern approaches in materials science should provide a solution to the problems of energy and resource conservation. They are also called upon to develop a line of directed synthesis of composites that possess the required parameters over the entire spectrum of properties. In order to obtain a high-strength structure of a clinker-free binder, the possibility of obtaining it on the basis of natural gypsum stone is considered. As is known, the strength of crystallization structures by adhesion in contact and the number of contacts is determined. To optimize the internal structure of a high-strength clinker-free binder, to obtain the maximum number of contacts and increase their strength, the possibilities of geometric topological approaches were used. When solving such problems, the geometric parameters and organization levels of the structures of disperse systems allow topology to be described. The fundamental possibility of obtaining a high-strength composite structure through the prism of the formation of a dispersed system with a maximum number of phase contacts between crystals of calcium sulfate dihydrate is considered. The granulometric composition of gypsum stone must meet the requirements (principles) of hardening, physical-chemical model and type of structure. Therefore, in the work, the possibility of obtaining high binder strength by optimizing it in accordance with the model was studied. mixtures of two powders with different average particle sizes were used. This increases efficiency and improves the properties of the binder.

In the present work the receiving of gypsum products on the basis of a calcium sulfate dihydrate is described. As a raw material, the calcium sulfate dihydrate in the form of industry waste was used. This research offers the mechanism of un hydration hardening of monomineral bindings, including gypsum. The mechanism is based on interaction of particles of the different size in the conditions of supersaturation when pressing. Under the corresponding conditions in system of a dihydrate crystallizational contacts are formed. The offered mechanism is confirmed with pilot studies. Researches of solubility of powders, to deformations of raw mix, strength, density and other characteristics of structure are conducted. Strength reaches to 74 MPa. The way allows to simplify technology of receiving gypsum products. Expenses of energy decrease. Burn is excluded and the grinding is reduced. Thus the offered of un hydration hardening of monomineral binders has high innovative appeal.

The paper shows the results of studies of gypsum dispersed systems with the addition of waste production of basalt. Introduction basalt dust allows the physical and mechanical properties of the modified gypsum material. The effect of additives on the strength, density and water absorption of gypsum dispersions hydration hardening.

This paper examines the possibility of simulating the structure of gypsum composite modified with basalt dust waste to make materials and products based on it. Structural simulating of the topological space in gypsum modified composite by optimizing its grain-size composition highly improves its physical and mechanical properties. Strength and density tests have confirmed the results of the simulation. The properties of modified gypsum materials are improved by obtaining of denser particle packing in the presence of hemihydrate of finely dispersed basalt and plasticizer particles in the system, and by engaging basalt waste in the structuring process of modified gypsum stone.

Conventional construction materials used in building industry is one major contributor to the increasing amount of greenhouse gases (GHG) and other pollutants in the atmosphere, which is responsible to the worsening effects of climate change and other threatening environmental issues worldwide. In addressing this alarming situation, construction key players must apply strategic development and consider the exploration of alternative materials, methodologies, and energy-saving measures for both new and old buildings. The application of Life Cycle Analysis (LCA) is one recommended initiative to identify, analyse, and compare the environmental impacts of traditional and new alternative materials used in the industry. In this study, with the integration of Building Information Modelling (BIM) tool to Life Cycle and Cost Analysis (LCCA), the environmental impact and total construction cost of different partitions walls namely concrete hollow blocks (CHB), gypsum drywall, foamed concrete, and foamed geopolymer wall have been efficiently analysed and compared. Based on the results of LCA, significant values had been observed on the six environmental impact categories namely fossil resource scarcity, land use, human non-carcinogenic toxicity, human carcinogenic toxicity, terrestrial ecotoxicity, and global warming. Concrete Hollow Blocks (CHB) wall exhibits greater impact on fossil resource scarcity, foamed concrete wall to land use and global warming, and dry wall to human non-carcinogenic toxicity, human carcinogenic toxicity, and terrestrial ecotoxicity categories. On the other hand, cost analysis shows that among all partition walls, the construction of CHB wall gave the lowest total cost value while the construction of foamed geopolymer wall costs the highest. Overall, results of this study indicate the potential use of other alternative materials to achieve sustainability in the building industry. [ABSTRACT FROM AUTHOR]

This paper presents the results of comparative studies of the effect of highly dispersed fillers on the mechanical and structural characteristics of pressed composites based on gypsum. As microfillers, powders of metakaolin and the ash were introduced into the composition of the gypsum mixture. The active component in the form of metakaolin affects the structure and properties of pressed stone. The average median grain size of metakaolin predetermines an increase in packing density due to the filling of voids between larger particles of gypsum with a highly dispersed phase. The effect of increasing the density of the modified composite has been established. Studies of water absorption of stone with the addition of metakaolin have established an increase in water resistance and a decrease in water absorption of a modified composite. The results of studies of gypsum with ash additive confirm the effectiveness of the introduction of the ash in terms of strength and density. As in the case of metakaolin. Gypsum with the addition of ash has not only increased density and, as a result, high performance, but also high creep resistance. Based on the results of the microstructural and spectral analysis of pure and modified stone, a comparison was made of the elemental composition of the original stone and the modified composite on the grain surface and in the contact zones of gypsum particles with particles of fillers. They confirm the participation of additives in the formation of crystallites of the composite and the mechanical compaction of its structure. [ABSTRACT FROM AUTHOR]

Any period of high temperature in which special precautions need to be taken to ensure proper handling, placing, finishing, and curing of concrete. High winds, low relative humidity, and solar radiation all have major effects on concrete. Hot weather conditions can produce a rapid rate of evaporation of moisture from the surface of the concrete and accelerated setting time, among other problems. Generally, high relative humidity tends to reduce the effects of high temperature, because of hot and dry climate in the Iraq has been the addition of the gel to the mixture of concrete for keeping the water into the concrete during solidification and prevent cracks. Through the results, it showed an increase in the moisture content in the samples who containing a certain percentage of the gel in (7-28) days with the increase in the resistance ratio (strength of the concrete).

Basalt fiber can serve as a substitute for synthetic fiber in gypsum-reinforced materials. Similar installation materials have been used in the Green Installation Programme. Other types of fibre, including basalt dust, that have not previously been considered are also attracting much attention. It forms during dry dust removal and is an available waste from the production of basalt materials. In addition to industrial dust wastes, it is proposed to use recycled bottom ash as a dispersed filler as an additional component. During its processing, coarse fractions were removed from the ash and the content of the organic part was reduced. The purpose of this study is to explore the possibilities of an organomineral complex of additives based on basalt dust, recycled bottom fuel ash and a hyperplasticizer Melflux 2641F to improve the properties of gypsum materials. Varying the components of the organomineral complex causes a change in the properties of the resulting composition: increasing the density and compression and rupture strength, reducing water absorption. An increase in the physical and mechanical characteristics of the gypsum composite with the introduction of basalt dust and bottom ash is associated with obtaining a denser particle due to an optimally selected granulometric structure and obtaining effective gypsum composites with an optimized internal structure. The microscopic structure of the modified gypsum composite with an organomineral complex of additives was established using scanning electron microscopy (SEM). The organomineral complex changed the structure of the gypsum stone and energizing the formation of intergrowth contacts with each other. [ABSTRACT FROM AUTHOR]

The paper shows studies of dispersed systems based on cement binder and dispersed aluminosilicate filler. Such dispersed filler in research is modified waste - ash from a thermal power plant from the Moscow region. This waste was generated by hydraulic ash removal. In the work ash was used, which has undergone additional training. It was divided into separate components. In these studies, an aluminosilicate component was used. It has fairly stable chemical and physical-mechanical properties. The treatment of ash powder proposed in this work makes it possible to obtain a system with a large number of contacts in a dispersed system. In this work, the effect of mechanical activation of ash-cement compositions on the physical and mechanical properties of cement stone is investigated. It is shown that in the process of additional grinding, the destruction of large-pore particles occurs. They may be present in small amounts in the ash after processing. The use of activated ash in cement compositions affects the properties and structure of the cement stone. This is facilitated by the active interaction of Portland cement minerals with aluminosilicate ash components. Highly dispersed particles of activated ash in the dispersed binder system allow you to regulate the internal structure of the stone. The highly dispersed composition of the ash powder requires additional plasticization of the dispersed system. The additional introduction of a plasticizer into the activated ashcement composition helps to improve rheological characteristics, and, consequently, to increase the strength and density of the modified cement stone with the addition of highly dispersed ash filler. [ABSTRACT FROM AUTHOR]