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Due to renovation and fighting in the world, a huge accumulation of construction and demolition waste is formed. These materials are effectively used as aggregates, but there is very little information about the use of scrap concrete to create cementless binders. The purpose of the work is to be a comprehensive study of the composition and properties of concrete wastes of various fractions with the aim of their rational use as cementless binders. The scientific novelty lies in the fact that the nature of the processes of structure formation of a cementless binder based on sandy fractions of the screening of fragments of destroyed buildings and structures, as a complex polyfunctional system, has been theoretically substantiated and experimentally confirmed. Different percentages of non-hydrated clinker minerals in concrete scrap were determined. In the smallest fraction (less than 0.16 mm), more than 20% of alite and belite are present. Waste of the old cement paste is more susceptible to crushing compared to the large aggregate embedded in it, therefore, particles of the old cement paste and fine aggregate predominate in the finer fractions of the waste. Comprehensive microstructural studies have been carried out on the possibility of using concrete scrap as a completely cementless binder using scanning electron microscopy, X-ray diffraction analysis, and differential thermal analysis. It has been established that for cementless samples prepared from the smallest fractions (less than 0.315 mm), the compressive strength is 1.5–2 times higher than for samples from larger fractions. This is due to the increased content of clinker minerals in their composition. The compressive strength of the cementless binder after 28 days (7.8 MPa), as well as the early compressive strength at the age of 1 day after steaming (5.9 MPa), make it possible to effectively use these materials for enclosing building structures.

Currently, the topic of improvement of man`s live ability is becoming increasingly important. The notion of luxury living in the city includes social comfort, environment comfort (urban, natural landscape component). A wide range of small architectural forms of different architectural design and purpose is developed. The basic material for the production of small architectural forms is concrete. On optimal combination of negative and positive qualities, concrete is the most cost-effective material. In order to avoid increasing the price of hardscape, at their creating, it`s actual to use local raw materials and industrial waste. On their basis the modern high quality building materials are developed. To reduce prime costs of construction materials the technogenic raw materials are used. The solution of this actual problem possibly on the basis of expansion of a source of raw materials of the stone materials suitable for production of filler. Use of fine-grained concrete is perspective. This look allows to receive high-quality structure of a material, differs high technological effectiveness, allowing it is rather simple to make products as a pressing method with immediate striking, and it is easily and effectively modified by a molding method that is especially convenient for monolithic housing construction, and, besides, by means of organic-mineral modifiers, providing materials with various use of cheap local sand that allows to reduce concrete cost by 15-20% in comparison with coarse-grained concrete on rubble.

This paper discusses some of the major environmental problems of North-Arctic region. It has been proposed to use provisions of Architectural geonics and "green" composite compounds with nanodisperse organic mineral additive to improve the ecological situation in the region and enhance the effectiveness of the "Man-Material-Habitat" system.

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It is necessary to solve the ecological problems of regions where there is large-tonnage storage of various finely dispersed materials, including technogenic ones. This article presents the results of an investigation into the possible use of substandard dispersed quartz sands to obtain effective granular aggregates, with the purpose of putting them to use in mortars and concrete. The study used standard and original experimental research methods related to the analysis and preparation of raw materials, technological tests, and the study of the properties of finished composites. Investigations were carried out to obtain composite binders in the component composition of which the use of different ratios of Portland cement and substandard quartz sands prepared in a vortex jet mill was envisaged. It was found that the obtained composite binders had high physical and mechanical characteristics, which was due to the high specific surface area and hydration activity. On the basis of composite binders and finely dispersed quartz sands (fineness from ≤0.16 mm to 1 mm), the granulation of mixtures of 36 types of component compositions was performed. The developed compositions of granular aggregates (GAs) showed the possibility of obtaining them with sufficiently high strength values in cement stone. The studies carried out make it possible to recommend finely dispersed substandard and technogenic materials for the production of GAs, which would ensure the economy of binding materials as well as contribute to the reuse of large-tonnage waste of ferrous and nonferrous metallurgy and the chemical and mining industries.