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The article is devoted to the characteristics of foam concrete with the application of nanostructured binder (NB) on the basis is amorphous aluminosilicate rocks. The optimal technological parameters of the production of nanostructured perlite binder (NPB) were stated. The selection of foam generating agents was accomplished and mechanisms of formation of cellular composites on the basis of NPB were studied. Physical and mechanical characteristics of the obtained material were determined.

The combined interaction of factors is presented determining the principles of creating nanostructured binders based on highly concentrated ceramic binder systems (HCBS). Presence in HCBS of particles at a nano-level, and also intentional optimization of the spatial structure of this system has a comprehensive favorable effect on structure, rheotechnological properties of HCBS, and the technical and operating properties of materials prepared based upon them.Creation of a new generation of high quality materials is impossible without controlling the process of structure formation at the micro-and nanolevel. Practical interest in nanosystems in the area of material science of ceramics and refractories is due to the possibility of creating rational composite structures as a result of their significant modification with a change-over to the nanolevel accompanied both by a fundamental change in the properties of traditional materials and the creation of neocomposites.However, use of nano-objects in existing technology is connected with certain difficulties, including the following. As particle sizes are achieved close to the nanolevel, there is a considerable reduction in their packing density, and preparation of dense materials is accompanied by considerable shrinkage. A more promising version from a technical point of view may be consideration of the presence in a composite of a small content of nano-dispersed particles, an example of which is a highly concentrated ceramic binder systems (HCBS). In addition, currently in view of the increasing requirement for effective binder substances, including binders of the unhydrated hardening type and materials based on them, exhibiting high operating properties, it is important to develop a new class of nanostructured binders with a capacity to partly or completely replace cement in molding systems over the maximum broad range of material classes.HCBS technology is one of the newest areas in contemporary material science, whose theoretical basis was developed by Yu. E. Pivinskii. HCBS are mineral aqueous suspensions, obtained primarily by wet grinding of natural or technogenic silica, aluminosilicate or other materials under conditions of a high solid phase concentration, increased temperature and limited dilution. These conditions on one hand promote "production" in a system of a specific amount of nanoparticles (gel, obtained by dispersion), and on the other hand provide mechanical activation of particles of the main solid phase. Solidification of these systems and their strength are based predominantly on a contact-polycondensation method. In view of this in creating HCBS the task was resolved of realizing under industrial conditions a capacity for the original raw materials for spontaneous polymerization structure formation [1,2].The limited application of these systems is due to the dilation properties inherent for them, that considerably reduce the possibility of choosing a compaction method for a molding mix based on HCBS, and complicate the production technology for ...

Normally, the component composition of building materials makes a significant contribution when formation of final performance properties of them. Moreover, new types of binding systems, in spite of their poor knowledge, this effect on the structural characteristics of final composites also takes place. In this work, perlite-based geopolymer binder as an example, was studied. In framework of the study, it was found that the application of grinding mill with a metal lining leads to the formation of Fe- milling yield, which is included into crushed raw materials (perlite) com-position. It was established that the particles of the resulting Fe- component are nanoscaled. The X-ray phase and chemical analyzes were used to determine the mechanism of the effect of the Fe- component on the properties of perlite-based geopolymer. Microstructure of the hardened geopolymer paste were studied using SEM microscopy. Phase and mineral composition of geopolymer paste obtained by XRD-analysis showed, when the hardening process, nanosized iron hydroxide or bernalite Fe(OH)3(H2O)0.25 is formed in the geopolymer system, that is 5 times more than metallic iron. This is initiates the structure destruction and confirmed by the low values compressive strength of the geopolymer stone. Keywords: Fe-bearing component, metallic milling yield, geopolymer binder, friable structure, the Scherrer formula

This article deals with the development of autoclaved composites (AC) with nanostructured additive (NSA) and reports on the beneficial effects of NSA in autoclaved lime-silica mixtures.Based on the results of X-ray diffraction and electron microscopy investigation, the effects of hydrothermal conditions on the mechanisms of lime-silica interaction are revealed. It is demonstrated that the addition of NSA intensifies the formation of the C-S-H phase, reduces the quantities of amorphous phases and enables the formation of low-base calcium hydrosilicates (11Å-tobermorite and xonotlite).The physical and mechanical properties of autoclaved composites with NSA are investigated and optimized. The reported research demonstrates the feasibility of NSA application to improve the performance of autoclaved materials.