Nanotechnologies in Construction: A Scientific Internet-Journal

313-319

Authors: Zhukov A.D., Bobrova E.Yu., Bessonov I.V., Medvedev A.A., Demissie B.A.

In the areas of construction materials science, the most promising solution is a set of issues related to the study of the influence of conditions for the formation of the material structure, including the possibilities of its self-organization, on its properties. The chemical and physical aspects of this influence are studied at the micro level, using the entire complex of “subtle” studies. At the same time, there are methods that allow us to assess the possibility of nanoeffects in experiments carried out at the macro level: in production or in the laboratory. One of these methods is the method described in the article. The main provisions of the methodology have been formed on the basis of statistical methods for conducting experiments and studying technological processes. This technique can significantly reduce the number of experiments performed while maintaining the adequacy of the results obtained and makes it possible to perform further analytical optimization of the results and their engineering interpretation. In particular, application of this technique allows evaluating joint influence of various factors on the result, that makes it possible to identify synergistic and antagonistic effects and then test them at the micro level by studying the nanostructure of materials.

331-338

Authors: Ivanov L.A., Xu L.D., Bokova E.S., Ishkov A.D., Muminova S.R.

The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention «A method to produce dry construction mixtures» refers to manufacturing of building materials, in particularly, to manufacture of dry construction mixtures (DCM) by the method of joint mechanoactivation of cement and dolomite, with further modification of them with carbon nanostructures (CNT). The technical result of the given method of mixing CNT and main component of dry construction mixtures - cement – is that it makes possible to use microquantities (0.005%) of CNT in DCM. That allows decreasing product cost of obtained mixture. Moreover, due to increased strength, faster hardening of materials one can reduce consumption of these mixtures. That is additional factor affecting decrease of mixture product cost. The results obtained after application of mechanoactivation of basic mixture components were different practically by all indicators from the mixtures prepared by simple mixing. Compression strength and tensile strength increased by 10–15%, adhesion strength increased too. Along with increasing of strength characteristics such an important indicator of DCM as air permeability has decreased. Reduction of total volume of pores in dense structure of cement matrix caused dramatic slow-up of moisture diffusion rate.

250-255

Authors: Khalikov R.M., Ivanova O.V., Korotkova L.N., Sinitsin D.A.

The use of modifying nano-additives in the production of binding building materials is one of the most effective ways to control the technological parameters of concrete by conducting good control of the rheological characteristics reliability. Plasticizing additives increase the water-holding capacity of building compositions, which leads to the dispersed nanosystems stability. This article is focused on examining the physical and chemical mechanisms of the supramolecular effects of polycarboxylate ethers on technological and rheological characteristics of cement nanobinders. Methods and materials. This study describes controlled hardening processes of concrete nanocompositions with demanded technological characteristics in the presence of highly effective plasticizers. Moreover, this paper carries out the analysis of the innovative trends in regulating the consistency of building nanocomposites with the use of new comb-like polycarboxylate esters, which as superplasticizers allow to purposefully influence the kinetics of structure formation of cement nanocomposites. Results. Electrostatic and steric repulsion mechanisms, as well as the dispersing effects of innovative and traditional plasticizing nanoparticles, affect the adsorption and diffusion layers of the hydrated cement nanobinders ultrastructure. The most effective plasticizing properties are shown by comb-like polycarboxylate esters (CPE) with a linear chain molecular weight of ≈12000 g/mol and a length of side branches which correspond to a molecular weight of ≈750 g/mol. The supramolecular mechanism of nanosteric van der Waals repulsive forces begins to be detected at a distance of ≈11 nm, and the elasticity of the lateral branches of innovative CPE is ≈ 5 nm. Individual segments of CPE macromolecules enter the diffuse layer of dispersed nanosystems due to lateral interactions of anions of functional groups, hydrophobic fragments, etc.; they enhance the plasticizing effect of cement binders in concrete nanocompositions. Discussion. When using superplasticizing CPE, the density of concrete nanocomposites can be increased by reducing the amount of water mass to the cement mass ratio to the optimal 0.3; at the same time, technological pumpability and reliability control of the joint hardening kinetics with fillers are preserved within the framework of the technological problems system solutionsconcept. Supramolecular interaction of «anchoring» functional groups of polyacrylic acid containing solid phase cations of cement microparticles, fractal clusters of calcium hydrosilicates and simultaneous steric stabilization of polyethylene glycol radicals give the necessary rheological characteristics to construction nanocompositions and allow the construction of high-strength 55÷80 MPa building materials. Conclusions. The branched comb-like nanostructure of polycarboxylate esters exhibits effective technological characteristics of superplasticizers for concrete, building mortars and dry building mixes.

275-284

Authors: Ivanov L.A., Ishkov A.D., Pisarenko Zh.V., Wang Q., Prokopiev P.S.

The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention “Heat-insulating material based on air gel” can be used to obtain heat-insulating materials for a wide range of applications. The required technical result, which consists in improving the thermal insulation properties of the material in a wide temperature range, increasing the absorbing properties of electromagnetic radiation in the IR spectrum, increasing the mechanical strength and flexibility, as well as reducing crumbling, is achieved in an air gel-based material containing a fibrous substrate with a density of 0.001–0.1 g/cm3, consisting of silica and/or glass and/or basalt fibers with a diameter of 0.1–5 microns, which is impregnated with an air gel obtained on the basis of silicon dioxide from alkoxysilane with the introduction of a gelling agent and followed by supercritical drying. The introduction of nanomaterials gives an additional reinforcing effect, which increases the mechanical strength of the final material and significantly reduces the crumbling of the air gel. The final material can be provided with an additional layer of fibrous substrate to increase its vibration resistance. This is especially true when using the proposed material for civil and industrial construction in seismically active zones, as well as in aircraft and rocketry. The specialists can also be interested in the following inventions in the area of nanotechnologies: nano-coating protection method for electrical connectors, preparation method of nanometric size metal oxide additives that reduce the temperature of sintering, raw material mixture for the manufacture of fine-grained polymer concrete (modified with microsilica), installation for the synthesis of carbon-containing nanomaterials, a method for producing silver nanoparticles, a method for producing nanocrystalline cubic tungsten carbide, a composition with carbon nanotubes for obtaining a carbon blank for high-density SiC/C/Si ceramics and a method for producing articles from SiC/C/Si ceramics, composite membrane for drying natural and technological gas mixtures based on graphene oxide intercalated with hydroxylated fullerene derivatives, compositions containing nanometric copper, carbon-ceramic fiber-reinforced composite material and a method for its production, a method for producing nanoparticles of aluminum oxide et al.

204-210

Authors: Mazitova A.K., Sukhareva I.A., Sidorov G.M., Abdrakhmanova L.K.,Кuznetsova E.V.

The sewer of woodworking enterprises in the construction industry are characterized by a high content of suspended and dissolved toxic substances, including phenol, and a high value of chemical oxygen consumption (COD). At the same time, some enterprises do not have their own local treatment facilities and need to develop their own integrated treatment systems. One of the effective methods for removing pollution is wastewater ozonation, used in three versions: flocculation with small doses of ozone (pre-ozonation) at the initial stage to remove suspended substances, oxidative ozonation and decontamination. However, methods for treating wastewater from wood processing plants using ozone have not been sufficiently studied. Therefore, we investigated the flocculating effect of ozone in the process of cleaning the effluents of the plywood-plate mill, tested the effect of the dose of ozone during flocculation in the presence of a small number of coagulants VPK-402 and Kaustamine-15 on the concentration of suspended substances, phenol and COD value.

223-231

Authors: Pisarenko Zh.V., Ivanov L.A., Wang Q.

The construction industry has long been regarded asenergy-intensive and high pollution industry. The emergence of nanotechnology provides an ideal solution for the construction industry to energy saving and consumption reduction. The introduction of nanotechnology has greatly promoted the development of new green building materials and brought huge economic and social benefits. This paper applies bibliometric analysis to review the nanotechnology-construction research collected by Web of Science database during 2000–2020, and further visualize their literature characteristics. At the global level, the number of literatures on nanotechnology-construction research has been on the rise in 2000-2019, although it has experienced a small decline in individual years. At the national level, the United States has become the global leader in nanotechnology-construction research with 63 articles, far more than other countries. Considering the income gap, developed countries play an indispensable role in the global nanotechnology-construction research system, while the role of developing countries is relatively weak. We found that the existing nanotechnology-construction research mainly focused on the fields of chemistry and materials science. According to the frequency of keywords, the research focus of nanotechnology-construction research mainly focused on the development and application of new building materials. It is concluded that with the extensive attention of researchers, the future research on nanotechnology-construction will continue to appear and increase at increasing rate.

140-146

Authors: Ivanov LA., Demenev A.V., Pisarenko Zh.V., Wang Q.

The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention «Raw mixture for production of fine-grained polymer concrete modified by microsilica» refers to construction and can be used in manufacture of nanomodified concretes based on potentially chemically reactive coarse and/or fine filler for transport, industrial and civil construction. Modification of cement stone structures by means of microsilica made of silica production wastes and acrylic dispersion will make it possible to intensify hydration of binder, to reduce cement consumption and to increase strength characteristics of final product compared to traditional concrete mixtures. The invention can be used to produce concrete articles and structures, flagstones, decorative borders, to arrange top layers of road beds and to repair them when it is required, as well as to fill cracks and as a filler in sealing joints. The specialists can also be interested in the following inventions in the area of nanotechnologies: nanomodified high-strength light concrete, combined heat-insulating system, composite layered self-healing material, a method to produce metal/carbon nanocomposites, an electrochemical method to produce nanosized powder of metal silicide, a method to produce metal-polymer nanocomposite materials with metal nanoparticles et al.

160-165

Authors: A.M.Boldyrev., Sizintsev S.V., Sannikov V.G., Pershin V.F.

Steel constructions are the most important objects of the construction industry. The main method of connecting individual elements and assemblies of such structures is fusion welding (electric arc, plasma, electron beam). One of the main problems of metal structures is their tendency to brittle fractures that occur suddenly, without noticeable previous deformations, often at below zero temperatures and loads. In this case, 70–80% of such damage is associated with welding. The nature of the destruction depends not only on temperature, but also on the type of crystal lattice. Metals with a body-centered cubic (bcc) lattice (tungsten, molybdenum, α-iron) are plastic at a relatively high temperature, but become brittle when negative. And metals with a face-centered cubic (fcc) lattice (aluminum, nickel, copper and γ-iron) are plastic even at temperatures close to absolute zero. With decreasing temperature, the mobility of dislocations and vacancies decreases, the yield strength σs increases, that is, the ductility of the metal decreases. Using the A.F. Ioffe model showed that the critical temperature of the transition from viscous to brittle fracture with decreasing temperature depends on the rate of increase of σs. In austenitic steels (fcc lattice with a period a = 0.3645 nm), the impurity mobility (paired with a vacancy) through the internode of the lattice is higher, and the growth rate σs is lower than that of low-carbon low alloy steels (bcc lattice with a shorter period a = 0, 2861 nm). Therefore, the low carbon steels from which structures are made are more sensitive to lower temperatures. In addition, resistance to brittle fracture depends on the number and size of metal continuity defects (pores, inclusions, low-plastic phases in the structure, etc.), which are stress concentrators. Welds are the main suppliers of such dangerous defects and sources of crack initiation. During crystallization of the weld pool, a coarse, columnar dendritic structure with reduced ductility is formed. The formation of a fine-grained structure of the weld during crystallization helps to increase its ductility. The grain size in the cast metal (in the weld) depends on the crystal growth rate and the rate of their nucleation. When welding, the most effective way to grind the grain in the seam is to increase the rate of nucleation. The introduction of refractory particles of nanoscale order into the weld pool (nanomodification) allows obtaining a fine-grained weld structure.

174-184

Authors: Belozerov V.V., Golubov A.I., Kalchenko I.E., Nguyen T.A., Topolsky N.G.

Introduction. The aim of the study was to optimize the quality control of fire retardant coatings (FRC) during their production and use. The results of a comparative analysis of the consequences of fires and their causes with the parameter of fire resistance of objects indicate that the number of fires and damage from them in buildings of the first degree of fire resistance is almost an order of magnitude smaller than in buildings of the second degree of fire resistance. Consequently, increasing the fire resistance of building materials and structures is the way to radically reduce fires and losses from them. Methods and materials. Based on a system analysis of existing fire protection technologies for building materials made of wood, metals, rubber and polymers, nanotechnologies were developed to determine the stability of samples with an FRC on the baro-electro-thermo-acoustic (BETA) analyzer and create their «images» for further diagnosis of their aging at the constructions and operation facility. The novelty of the study is protected by patents of the Russian Federation. Results and discussion. The obtained results consist in the refinement of computational algorithms for the FRC in the BETA analyzer, as well as in the development of a portable automated complex, which allows to determine the stage of «aging» of the FRC on these materials, and, consequently, their durability and update time. This conclusion is based, firstly, on the results of the development of a thermo-electro-dilatometer crucible for controlling liquid and viscous materials by the authors of the «float design», which will make it possible to control the FRC characteristics during their production, and secondly, to carry out express control after filling them in containers (polymer, metal, glass) without opening it and thirdly, due to the recognition of these «images» using thermo-electro-measurements of the FRC using special probes connected to a portable automated system. Conclusion. The results obtained make it possible to «arm» with portable automated systems not only construction and fire control authorities, but also manufacturers of emergency protection products. This will allow, according to the authors, to fundamentally solve the problems of quality and durability of FRC, but the main thing is to guarantee the stability of the protected materials and structures from them.

71-76

Authors: Ivanov LA., Kapustin I.A., Borisova O.N., Pisarenko Zh.V.

A brief review of patents is given. The research performed by scientists, engineers and specialists in the area of nanotechnologies and nanomaterials resulted in increased efficiency of construction, housing sector and adjacent fields of economy.For example, an invention «A method to produce metal-polymer nanocomposite materials with metal nanoparticles» refers to the method used in production of polymer articles with nanoparticles of silver or copper, widely applied in different engineering areas and used as antibacterial material. The invention provides environmental responsible and reagentless method to obtain polymer articles with metal nanoparticles which size is 5–15 nm and boosts rangeof polymers, including hemicrystalline and amorphous glass-like ones. The invention «Exfoliated polyurethane nanocomposite with polyfluoroalkyl groups» refers to design of composite and nanocomposite materials and can be used to create materials applied in polymer industry, in particularly, in production of solidcoatings for sport facilities, hydroinsulation and roof coatings, construction sealers and tribotechnical articles. The specialists can also be interested in the following inventions in the area of nanotechnologies: a method to obtain metal nanopowder from lead bronze wastes in distilled water, a method to produce collector plates, a water defluoridation method,an exfoliated polyurethane nanocomposite with polyfluoroalkyl groups, amultifunctional grease lubricant for heavy loaded friction joint, a thermostatic system to perform nanocalorimetric measurements, a self-hardening composition based on polydimethylsiloxane et al.

89-93

Authors: Levin Y.A., Nikitin A.A., Konotopov M.V., Ivanov L.A.

The article explores the possibility of using nanotechnology to improve the efficiency of centralized and autonomous heating systems on the way to a new technological model. A logical sequence of the development of heat supply and heating is given, conservative equipment and technologies that are used to supply thermal energy to consumers is marked. In the context of the urgent tasks of heat supply and heating of buildings, the concepts of the use of nanotechnologies that meet the goals of maximum heat transfer intensification are considered. Heat conduction analysis, concentration, size, mass and velocity of nanoparticles assesses are the basis for assessing the possibility to use nanofluids as a coolant for improving heat exchangers and to reduce heat losses in heating systems to maximize efficiency of their work. It is shown that the use of nanostructures affects the saving of coolant flow as the main task of the qualitative and quantitative regulation of the heat supply system. Attention is focused on the application of nano-structured materials in low-temperature fuel cells used decentralized heating systems for heating houses.

100-107

Authors: Sergeev V.V., Sharapov R.R., Kudymov A.Y., Zeigman Y.V., Mukhametshin V.S.

Colloidal systems in form of emulsions or suspensions are widely used in various of industries including oil-gas fields development industry. Invert emulsions and suspensions are actively applied in fields development, including enhanced oil recovery, intensification of oil production, drilling and wells workover. Results of laboratory tests for studying physical properties of heterogeneous systems as an emulsion system with nanoparticles and emulsion-suspension system with nanoparticles are presented in this paper. Having unique physical and chemical properties these systems can be effectively applied in upstream of oil and gas as a water-limiting agent or blocking pack with reversible effect. In framework of this research, laboratory tests for evaluation of the influence of the new systems on filtration characteristics of hydraulic fractures are carried out. Laboratory tests are planned in accordance with requirements of international standards and conducted under the closest conditions to subsurface thermal and pressure conditions of formations STyr Abdylovskoe, SBASh Yugomashevskoe and YuS-2 and YuS-4 of Tortasinskoe oil-gas fields. Based on the results, permeability and conductivity indexes of the models of hydraulic fractures before and after filtration of the new types of colloidal systems are calculated. In order to evaluate an efficiency of the new systems and to study a possibility to regulate its blocking properties an analysis of the impact made by a type and a quantity of nanosized solids on to the blocking properties is carried out. An optimal concentration of nanoparticles in the compositions for a range of formation conditions of particular carbonate and sandstone subsurface reservoirs of oil-gas fields of Russian Federation are represented in this paper.