Keywords: aluminosilicates

INCREASING IN IMPACT VISCOSITY OF FIBER-ASH-CONCRETE

https://doi.org/10.34031/2618-7183-2020-3-6-5-16
Abstract
The trend in building materials science is to replace the different proportions of Portland cement in the binder. Therefore, the paper proposes the principles of controlling the static and dynamic strength of fiber-reinforced concrete, consisting in the complex effect of the hydro-removed ash and slag mix and basalt fiber on the processes of structure formation of the cement composite. A four-stage purification system for the hydro-removed ash and slag mixture has been developed, including disintegration, flotation and two-stage magnetic separation. It was found that the density of the fresh mix from the dose behaves naturally, and the density of solid samples at low doses slightly decreases. High early strength of the developed composites is noted, in particular, for specimens with ASM, one and a half increase in compressive strength is traced in comparison with non-additive specimens. Combinations of "fiber + ASM" with a quadrupling of strength have a significant effect on bending strength. Successful approximations of the compressive strength and bending strength on the ASM dose for different ages (1, 7, 28 days) are traced with the regular behavior of the coefficients in the power dependences. Revealed a multiple increase in the impact strength of the developed compositions. The use of the results will lead to the possibility of designing high-strength concretes, including for special structures.
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STRUCTURE FORMATION IN ALKALI ACTIVATED ALUMINOSILICATE BINDING SYSTEMS USING NATURAL RAW MATERIALS WITH DIFFERENT CRYSTALLINITY DEGREE

https://doi.org/10.34031/2618-7183-2018-1-4-38-43
Abstract
The efficiency of traditional raw materials using as well as expanding of potential uses for non-conventional and alternative raw materials with different origin is the tasks exiting interest among material scientists and manufacture stuff. Investigation of the above is oriented on solution of such scientific problem as more deep understanding of structure and features of material. The results obtained also allow solution of some technological, technical and economical tasks.
Greatly, it is actual when using of new types of raw materials as well as when synthesis of new composites. Concerning the construction material science field, the classic problem is the looking for ways to study the reactivity of raw components under different conditions, its control and, generally, its increasing to produce higher performance materials.
Among the popular and widely-used construction materials are alkali-activated binders and relevant composites.
In this study the results of granulometric analysis of suspension based on alkali-activated aluminosilicate with different crystallinity degree are presented. It was found, when treatment of aluminosilicate grain by alkali activator leads to the grain solubilizing (but differently depending on crystallinity degree of aluminosilicate) and formation of alkali-aluminosilicate gel that reacts with unreacted part of the grain according to structure affinity principle. It was also determined the crystallinity degree of aluminosilicate component is inversely proportional to its solubility in highly-alkali environment. The model of structure formation for geopolymer system under alkali effect is offered.
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INFLUENCE OF THE GENETIC FEATURES OF SOILS ON THE PROPERTIES OF SOIL-CONCRETES ON THEIR BASIS

https://doi.org/10.34031/2618-7183-2018-1-1-69-77
Abstract
In order to form strong soil-concrete structures in parallel with the introduction of binder, an additive with a multicomponent composition that is activating the structure-forming process should be applied. Such addi-tive is usually called stabilizer of soil, its introduction allows achieving a positive effect for soils with a high proportion of finely dispersed fraction in its composition.
The article considers the main aspects of use in road construction of complex soil reinforcement by introducing a stabilizer and binding component. This technology will solve the problems of deficiency of high-quality traditional raw materials, lead to better physical and mechanical properties, increase labor productivity and reduce production costs.
As a result of the carried out studies, principles for improving the quality characteristics of reinforced soil were developed, taking into account the mineral composition of clay raw materials. As the main hypothesis of the study an increase in the hydrophobicity of stabilized soil by blocking the hydrophilic centers of clay rocks should be marked. This circumstance helps to reduce the consumption of cement in the reinforced soil without reducing the operational and physical-mechanical characteristics.
The dependence of the degree of effectiveness of the introduced stabilizing additive on the structural and chemical characteristics of clay rocks has been established, which decreases from montmorillonite and X-ray amorphous phases to kaolinite. Mixed layered formations, illite and chlorite act as intermediate minerals. Aluminosilicates act as the filler in this system that do not come into contact with the molecules of the stabilizer. To assess the degree of efficiency of interaction of the components of a soil-concrete mixture as an integral indicator it is necessary to use the cationic capacity of the soil.
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