R. HELA, Ph.D., L. BODNAROVA, Ph.D., T. JAROLIM, Ph.D.-student, M. LABAJ, Ph.D.-student Brno University of Technology (Faculty of Civil Engineering) (95, Veveri, Brno, 60200, Czech Republic)

Carbon Nanotubes Dispersion, Concentration, and Amount of Ultrasound Energy Required This article describes the possibilities and difficulties of carbon nanotube dispersion. Carbon nanotubes (CNT) have become a widely used material in medicine, pharmaceuticals, elec- tronics, and also in the construction industry. Thanks to using nanoparticles, we are able to improve the properties of ordinary materials such as coatings and concrete. CNT forms bun- dles which are not easy to disperse. The literature describes several ways to disperse CNT, for example, through intense mechanical grinding (ball mill), ultrasound (US energy), use of surfactants, hydro cavitation, or a combination of the above mentioned methods. This article describes the control of dispersion by ultrasound, with observation of the dispersion level through UV/Vis spectroscopy. Thus we established the optimal parameters of the dispersion. The data was then used to prepare the suspension water, CNT, and surfactants, which were then used for the preparation of cement mortars for the test specimens. The specimens were observed for their physical mechanical characteristics.

Keywords: carbon nanotubes, concrete, hydrodynamic cavitation, dispersion, UV/Vis spectroscopy.

For citation: Hela R., Bodnarova L., Jarolim T., Labaj M. Carbon nanotubes dispersion, concentration, and amount of ultrasound energy required. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 4–9. (In Russian).

Список литературы / References
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G.I. YAKOVLEV1, Doctor of Sciences (Engineering) (gyakov@istu.ru), Yu.O. MIKHAILOV1, Doctor of Sciences (Engineering), Yu.N. GINCHITSKAYA1, Engineer; O. KIZINIEVICH 2, Doctor-Engineer; P.A. TAIBAKHTINA1 , Master Student; Yu.A. BALOBANOVA1, Master Student 1 Kalashnikov Izhevsk State Technical University (7, Studencheskaya Street, Izhevsk, 426069, Russian Federation)
2 Vilnius Gediminas Technical University (11, Sauletekio, Vilnius, 10223, Republic of Lithuania)

The Construction Ceramics Modified by Dispersions of Multi-Walled Carbon Nanotubes The way of improvement of mechanical characteristics of construction ceramics by introduction to structure molding compound of dispersions of multi-walled carbon nanotubes (MWCNTs) is offered. This compounding material allows regulating structure formation of a ceramic matrix, thereby changing toughness index of ceramic samples. It is shown that introduction of MWCNTs exerts influence on structure of ceramics at the stage of green brick which further formation depends on burning temperature. According to test data at burning temperature of 1000 о C the homogeneous mix with the lowered content of pores is formed, the number of the pores interconnected is reduced. Use of molding compound of dispersions of MWCNTs in number 0,001% of clay mass allows improving physicomechanical index of the modified ceramics to 30% in comparison with check samples.

Keywords: ceramic, multilayeredl carbon nanotubes, nanomodification, strength indicators, porosity.

For citation: Yakovlev G.I., Mikhailov Yu.O., Ginchitskaya Yu.N., Kizinievich O., Taibakhtina P.A., Balobanova Yu.A. The construction ceramics modified by dispersions of multi-walled car- bon nanotubes. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 10–13. (In Russian).

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9. Bogdanov A.N., Abdrahmanova L.A., Hosin V.G. Modification of ceramic bodies plasticizing additives. Anniversary International Scientific Conference dedicated to the 60-th anniversary of BSTU named after V.G. Shukhov “High Tech and Innovation” XXI Scientific Readings. 2014, pp. 46–49. (In Russian).
10. Yakovlev G.I., Ginchitskaya Yu.N., Kizievich O., Kizinievich V., Gordina A.F. Influence of dispersions of multilayer carbon nano-tubes on physical-mechanical characteristics and structure of building ceramics. Stroitel’nye Materialy [Construction Materials]. 2016. No. 8, pp. 25–29. (In Russian).

K.A. KISLYAKOV, master, G.I. YAKOVLEV, Doctor of Sciences (Engineering), G.N. PERVUSHIN, Doctor of Sciences (Engineering) Kalashnikov Izhevsk State Technical University (7, Studencheskaya Street, Izhevsk, 426069, Russian Federation)

Properties of Сement Сomposition with Addition of Crushed Clay Brick and Microsilica The study focuses on the issues related to the use of crushed brick as a feedstock for producing construction materials. Crushed brick-based compositions with addition of microsilica have been investigated. Methods of DSC analysis, X-ray phase analysis and IR spectroscopy has shown that complex additive which includes brick dust and microsilica enters into reac- tion with the calcium hydroxide forming during hydration of Portland cement. This results in formation increase the strength of the compositions under study. The analysis of micro- structure with the use of the electronic focused-beam microscope has demonstrated that contributes to more homogeneous compact structure, adding of microsilica with crushed clay brick into the investigated slag-alkaline composition is accompanied by formation of additional low-basic calcium hydrosilicates.

Keywords: technogenic materials, crushed brick, cement binder, microsilica, calcium hydrosilicates.

For citation: Kislyakov K.A., Yakovlev G.I., Pervushin G.N. Properties of cement composition with addition of crushed clay brick and microsilica. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 14–18. (In Russian).

L.A. URKHANOVA, Doctor of Sciences (Engineering) (urkhanova@mail.ru), S.L. BUYANTUEV, Doctor of Sciences (Engineering) (buyantuevsl@mail.ru), S.A. LKHASARANOV, Candidate of Sciences (Engineering), A.B. KHMELEV, Engineer, A.A. URKHANOVA Engineer East Siberia state university of technology and management (40v, Kluchevskaya Street, Ulan-Ude, 670013, Russian Federation)

Modification of Cement and Concrete with Carbon Nanomaterials Obtained from Coal Cake The article presents the results of studies on the modification of the cement stone and concrete with carbon nanomaterials, obtained in two different units with the use of plasma and electric discharge technology. Revealed that the energy discharge unit is lower than that of plasma, but the effectiveness of the impact of supplementation with CNM obtained in plasma and discharge units, the properties of cement and concrete on its basis significantly different among themselves. Obtained as a result of the plasma and electric discharge treatment of coal cake carbon nanomaterials have been studied by electron microscopy, elemental, spectral analyzes. The introduction of carbon nanomaterials as a result of a complex interaction leads to a change in the phase composition and microstructure a cement stone and consequently improves the physical, mechanical and performance properties of concrete.

Keywords: plasma unit, electric discharge unit, coal cake, carbon nanomaterials, Portland cement, modified concrete.

For citation: Urkhanova L.A., Buiantuev S.L., Lkhasaranov S.A., Кhmelev A.B., Urkhanova A.A. Modification of cement and concrete with carbon nanomaterials obtained from coal cake. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 19–25. (In Russian).

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A.E.M.M. ELREFAEI 1 , Engineer, I.A. PUDOV 1 , Candidate of Sciences (Engineering) (pudovia@yandex.ru), G.I. YAKOVLEV 1 , Doctor of Sciences (Engineering) (jakowlew@udm.net); S.A. SENKOV 2 , Candidate of Sciences (Engineering); A.F. BURYANOV 3 , Doctor of Sciences (Engineering) (rga-service@mail.ru)
1 Kalashnikov Izhevsk State University (426069, Izhevsk, Studencheskaya Street, 7, Russian Federation)
2 Perm National Research Polytechnic University (614990, Perm, Komsomolskiy Avenue, 29, Russian Federation)
3 National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

Combining Additives of Various Genesis for Enhancing Modification of Concrete Currently, the main building material in construction is Portland cement-based heavy concrete. The paper studies the influence of different combinations of various superplasticizers, sil- icon dioxide and dispersion of multi-walled carbon nanotubes on the structure and properties of concrete. Combining the above additives in their optimal concentrations increases the strength after 7 days by 72–95%, after 28 days by 40–85% accordingly. Also, there is a change in the porosity parameters of the modified samples structure. The addition of complex additives is triggered the reduction of total porosity by 21–50%, decrease in the average pore sizes and a relative increase in the content of potentially closed pores. The differential thermal analysis of the cement matrix showed an increase of the total amount of calcium hydroxide due to the increased hydration of Portland cement in the modified concrete. The obtained data showed higher performance of the construction material.

Keywords: complex additive, modification, carbon nanotubes, superplasticizer, silicon dioxide, concrete, strength.

For citation: Elrefaei A.E.M.M., Pudov I.A., Yakovlev G.I., Senkov S.A., Buryanov A.F. Combining additives of various genesis for enhancing modification of concrete. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 26–30. (In Russian).

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S.V. LEONT’EV1, Engineer (n1306cl@yandex.ru), V.A. SHAMANOV1, Candidate of Sciences (Engineering) (vitshamanov@gmail.com), A.D. KURZANOV 1, Engineer; G.I. YAKOVLEV2 , Doctor of Sciences (Engineering) (jakowlew@udm.net)
1 Perm National Research Polytechnic University (109, Kuibysheva Street, Perm, 614010, Russian Federation)
2 Kalashnikov Izhevsk State Technical University (7, Studencheskaya Street, Izhevsk, 426069, Russian Federation)

Multiobjective Optimization of the Lightweight Autoclaved Aerated Concrete Modified with Carbon Nanotubes Dispersions The results of research aimed at obtaining of the thermal insulation autoclaved aerated concrete with the required level of the structure strength are presented in this article. The studies found that joint introduction in aerated concrete mixture of the specialized blowing agent with monodispersed particles, polycarboxylate and multi-walled carbon nanotubes dispersions to obtaining the enhance of strength properties of the thermal insulation autoclaved aerated concrete and slight decrease in its density and thermal conductivity by filling cracks crystal- line blocks tumors ordered structure and redistribution of the volume of micropores and capillaries in aerated concrete structure. Optimization of autoclaved aerated concrete composi- tion was performed by complex criterion of its quality by means of «Decon-SM» software product.

Keywords: autoclaved aerated concrete (ААС), thermal insulation, dispersion, multi-walled carbon nanotubes, optimization, complex criterion of quality.

For citation: Leont'ev S.V., Shamanov V.A., Kurzanov A.D., Yakovlev G.I. Multiobjective optimization of the lightweight autoclaved aerated concrete modified with carbon nanotubes dispersions. Название. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 31–40. (In Russian).

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15. Zakharov S.A., Kalachik B.S. The modern active mineral modifier of cement systems is a highly active metakaolin. Stroitel’nye Materialy [Construction Materials]. 2007. No. 5, pp. 56–57. (In Russian).
16. Yakovlev G.I., Pervushin G.N., Korzhenko A., Bur’yanov A.F., Kerene Ya., Maeva I.S., Khazeev D.R., Pudov I.A., Sen’kov S.A. Applying multi-walled carbon nanotubes dispersions in producing autoclaved silicate cellular concrete. Stroitel’nye Materialy. 2013. No. 2, pp. 25–29. (In Russian).
17. Yakovlev G., Pervushin G., Maeva I., Keriene J., Pudov I., Shaybadullina A., Buryanov A., Korzhenko A., Senkov S. Modification of construction materials with multi-walled carbon nanotubes. Procedia engineering. 2013. No. 57, pp. 407–413.
18. Kadashevich I, Schneider H., Stoyan D. Statistical mod- elling of the geometrical structure of the system of artifi- cial air pores in autoclaved aerated concrete. Cement and Concrete Research. 2005. No. 35, pp. 1495–1498.
19. Gitman M.B., Stolbov V.Yu., Fedoseev S.A. Organi- zational approach to product quality control. Standarty i kachestvo. 2012. No. 5, pp. 80–84. (In Russian).

K.A. SARAYKINA1, Candidate of Sciences (Engineering) (Ksenya_s2004@mail.ru), V.A. SHAMANOV1, Candidate of Sciences (Engineering), V.A. GOLUBEV 1, Candidate of Sciences (Engineering); G.I. YAKOVLEV2 , Doctor of Sciences (Engineering)
1 Perm National Research Polytechnic University (109, Kuibysheva Street, Perm, 614010, Russian Federation)
2 Kalashnikov Izhevsk State Technical University (7, Studencheskaya Street, Izhevsk, 426069, Russian Federation)

Prediction of Durability Basaltfiberconcrete Modified with Nanostructural Additives The article deals with durability basaltfiberconcrete (BFC), modified by nanostructural additives. The main durability criterion usually take frost resistance which depends of many fac- tors: the strength, density, water resistance, and others. Taking into account specificity of BFC, not less important durability criterion must be considered the safety of the reinforcing fiber in cement matrix. The investigations established the complex basaltfiberconcrete modification by nanostructural additives (high activity metakaolin and multi-walled carbon nano- tube dispersion) provides increased its durability and operating characteristics, due to the protection of basalt fiber from the alkaline corrosion by reducing the alkalinity, the contact zone of the seal basalt fiber – cement stone and control the composition and morphology of tumors cement matrix on the fiber surface.

Keywords: basaltfiberconcrete, reinforcing fibers, metakaolin, nanotubes, basalt fiber, corrosion, cement stone.

For citation: Saraykina K.A., Shamanov V.A., Golubev V.A., Yakovlev G.I. Prediction of durability basaltfiberconcrete modified with nanostructural additives. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 41–44. (In Russian).

References
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2. Kapitonov A.M., Red’kin V.E. Fiziko-mekhanicheskie svoystva kompozicionnyh materialov. Uprugie svoystva [Physical and mechanical properties of composite mate- rials. Elastic properties]. Krasnoyarsk: SFU. 2013. 531 p.
3. Pashchenko A.A., Serbin V.P., Paslavskaya A.P. and etc. Armirovanie neorganicheskih vyazhushchih veshchestv mineral’nymi voloknami [Reinforcement of inorganic binders in mineral fibers]. Moscow: Stroyizdat. 1988. 200 p.
4. Saraykina K.A., Golubev V.A., Yakovlev G.I., Politae- va A.I., Sen’kov S.A. Nanostructuring of cement stone at disperse reinforcing with basalt fiber. Stroitel’nye Materialy [Construction Materials]. 2015. No. 2, pp. 34–38.
5. Rabinovich F.N. Kompozity na osnove dispersno- armirovannyh betonov. Voprosy teorii i proektirovaniya, tekhnologiya, konstrukcii: monografiya [Composites based on fiber concrete. Questions of the theory and de- sign, technology, design: a monograph]. Moscow: ASV. 2004. 560 p.
6. Saraykina K.A., Golubev V.A., Yakovlev G.I., Fedoro- va G.D., Aleksandrov G.N., Plekhanova T.A., Duleso- va I.G. Modification of dasaltfiberconcrete by nanodis- persed system. Stroitel’nye Materialy [Construction Materials]. 2015. No. 10, pp. 64–69. (In Russian).
7. Bazhenov Yu.M. Tekhnologiya betona [The technology of concrete]. Moscow: Vysshaya shkola. 1987. 415 p.
8. Yakovlev G.I., Galinovskiy A.L., Golubev V.A., Sarayki- na K.A., Politaeva A.I., Zykova E.S. Nanostructuring as a method of adhesion properties increase of the «cement stone – basalt fiber reinforcement». Izvestiya KGASU. 2015. No. 2, pp. 281–288. (In Russian).
9. Granovskiy A.G. Strukturoobrazovanie v mineral’nyh vyazhushchih sistemah [Pattern formation in mineral binding systems]. Kiev: Nauka dumka. 1984. 299 p.
10. Aleksashin S.V. Increased frost resistance and water resis- tance of fine-grained concrete for hydraulic structures of rive. Cand. Diss. (Engineering). Moscow. 2014. 114 p. (In Russian).
11. Pudov I.A. Nanomodification of Portland cement with aqueous dispersions of carbon nanotubes. Cand. Diss. (Engineering). Kazan. 2013. 185 p. (In Russian).
12. Saraykina K.A., Golubev V.A., Yakovlev G.I., S.V. Sychugov, Pervushin G.N. The corrosion resistance in- crease of basalt fiber cement concrete. Stroitel’nye Materialy [Construction Materials]. 2016. No. 1–2, pp. 27–31.

V.G. SOLOVYEV1, Engineer (s_vadim_g@mail.ru), A.V. EREMIN1, Candidate of Sciences (Engineering) (aleks.eremin@gmail.com); D.M. ELISEEV 2, Engineer (eliseev@himsi.ru); А.F. BURYANOV1 , Doctor of Sciences (Engineering) (rga-service@mail.ru)
1 National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)
2 «Himsintez» OOO (5, Lihachevskiy Driveway, Dolgoprudniy, 141700, Russian Federation)

Improvement of Water Resistance of Gypsum Binder by Paraffin Emulsion The article describes the features of the influence of paraffin emulsions, which contain nano-sized particles, on fastness to water of gypsum binders of β-modification. The results of these studies show the effectiveness of paraffin emulsions “EMVAKS-GIPS-1” and “EMVAKS-GIPS-2”, containing nano-sized particles, to improve the fastness to water of products made of gypsum binders of β-modification – softening factor increased from 0.35 to 0.52–0.72. It is established that the main criterion of the effectiveness of paraffin emulsions gyp- sum binders of β-modification is the size of individual paraffin particles – a significant increase in efficiency is achieved when used with the paraffin emulsion particles less than 2 mkm, including nano-sized particles of less than 300 nm. Determined the features of structure of gypsum binders with introduced paraffin emulsions with different particle sizes.

Keywords: gypsum binder, paraffin emulsion, nano-sized particles, water resistance, structure.

For citation: Solovyev V.G., Eremin A.V., Eliseev D.M., Buryanov A.F. Improvement of water resistance of gypsum binder by paraffin emulsion. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 45–49. (In Russian).

References
1. Kozlov N.V., Panchenko AI, Buryanov A.F. Solo- v’ev V.G., Buldyzhova E.N., Galtseva N.A. Gypsum bind- ers improved water resistance on the basis of industrial waste. Nauchnoe obozrenie. 2013. No. 9, pp. 200–205. (In Russian).
2. Kozlov N.V., Panchenko A.I., Buryanov A.F. Microstructure plaster knitting the increased water resis- tance. Stroitel’nye Materialy [Construction Materials]. 2014. No. 5, pp. 72–75. (In Russian).
3. Gordin A.F., Yakovlev G.I., Polyanskih I.S., Keren H. Fischer H.-B., N.R. Rakhimov, Buryanov A.F. Gypsum compositions with complex modifiers of structure. Stroitel’nye Materialy [Construction Materials]. 2016. No. 1–2, pp. 90–95. (In Russian).
4. Patent RF No. 2381902 Sposob polucheniya vlagostoikikh izdelii na osnove gipsa [Мethod for producing a water-re- sistant gypsum-based products]. Veeramasuneni S., Kapakasa K. Declared 25.07.2005. Published. 20.02.2010. Bull. No. 5. 13 p. (In Russian).
5. Patent RF No. 2210553 Sposob polucheniya gipsovoi drevesnovoloknistoi produktsii s povyshennoi vodostoikost’yu i sposob polucheniya gipsovogo drevesnovoloknistogo lista s povyshennoi vodostoikost’yu [Method for producing gyp- sum wood fiber products with improved fastness to water and method for producing gypsum wood-fiber with in- creased to water]. Inglert Mark H. Declared 09.12.1997. Published. 20.08.2003. (In Russian).
6. Patent US 20130053481 Compositions, emulsions, and methods for making compositions and emulsions. Eduardo Romero-Noche Buena and etc. Declared 17.08.2012. Published 28.02.2013. 19 p.
7. Patent US 5437722 A Water-resistant gypsum composi tions and emulsion for making same. Lionel Borenstein. Declared. 01.03.1994. Published. 01.09.1995. 5 p.
8. Rale M.T. Was-based emulsifiers for use in emulsions to impart water repellency to gypsum wallboard. McMaster University. 2012. https://macsphere.mcmaster.ca/bit stream/11375/12612/1/fulltext.pdf
9. Wang F.F., Li G.Z., Liu M.R. Effect of waterproof emul- sion on properties of calcined gypsum from flue gas desul- furization. Advanced Materials Research. 2011. Vol. 168– 170, pp. 478–481.
10. Plotnikova G.P., Plotnikov N.P. Modification of wax emulsions for the production of particle boards. Sistemy. Metody. Tekhnologii. 2013. No. 2 (18), pp. 147–151. (In Russian).

V.V. STROKOVA, Doctor of Sciences (Engineering) (vvstrokova@gmail.com), D.D. NETSVET, Engineer, V.V. NELUBOVA, Candidate of Sciences (Engineering) (nelubova@list.ru), I.V. SERENKOV, Student Belgorod State Technological University named after V.G. Shukhov (46, Kostyukova Street, Belgorod, 308012, Russian Federation)

Properties of Composite Binder Based on Nanostructured Suspension This article describes the properties of the composite binder on the basis of nanostructured suspension. Portland cement is suggested to be used as modifying additive. Improving of physical and mechanical properties of obtained composite binder was justified. Addition of cement provides gain of strength more than 8 times that on the one hand is due to the sys- tem impaction, and on the other – due to the genesis of new crystalline formations as a result of hydration processes in the system. Here we give the description of change of rheo- tehnological properties of composite binder due to the presence of the active structuring component in the system. A substantial reduction of terms of drying of binder (up to 40%), which is one of the most important indicators of the quality of both the binder and the materials on its basis. The type of drying kinetics does not change. The obtained binder can be used for building composites for various applications.

Keywords: nanostructured binder, composite binder, modifier, structuring components.

For citation: Strokova V.V., Netsvet D.D., Nelubova V.V., Serenkov I.V. Properties of composite binder based on nanostructured suspension. Stroitel’nye Materialy [Construction materi- als]. 2017. No. 1–2, pp. 50–54. (In Russian).

V.G. KHOZIN, Doctor of Science (Engineering) (Khozin@kgasu.ru), R.K. NIZAMOV, Doctor of Science (Engineering) (Nizamov@kgasu.ru), Rector, L.A. ABDRAKHMANOVA, Doctor of Science (Engineering) (laa@kgasu.ru) Kazan State University of Architecture and Engineering (1, Zelenaya Street, Kazan, 420043, Russian Federation)

Modification of Construction Polymers (Polyvinylchloride and Epoxy) by Single-wall Carbon Nanotubes The article studies regularities of the structure changes in the process of modification of network (epoxy) and linear (polyvinylchloride) polymers and composites based on them by sin- gle-wall carbon nanotubes in the field of concentration up to 0.01%. For epoxy polymers the impact of tubes on the conversion degree of epoxy groups and on character of fast fracture is defined. For polyvinylchloride in concentration up to 0.001% it was found out the increase in strength properties with the rise of melt fluidity. Microstructure of epoxy polymer block sample cleavages studied my means of scanning electron microscope. Microstructure of 100 nm film PVC sample cross section is studied by transmission electron microscopy method. Localization of nanotubes in interstructural defect zones of polymers is also presented in the article.

Keywords: carbon nanotubes, polyvinylchloride, epoxy polymers, microstructure.

For citation: Khozin V.G., Nizamov R.K., Abdrakhmanova L.A. Modification of construction polymers (polyvinylchloride and epoxy) by single-wall carbon nanotubes. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 55–61. (In Russian).

V.I. KALASHNIKOV , Doctor of Sciences (Engineering), O.V. TARAKANOV, Doctor of Sciences (Engineering) (zigk@pguas.ru) Penza State University of Architecture and Civil Engineering (28, Germana Titova Street, Penza,440028, Russian Federation)

About the Use of Complex Additives in Concretes of a New Generation Issues of the technological design of high-strength concretes of a new generation with complex additives on the basis of up-to-date super-plasticizers and mineral fillers of different chemical-mineralogical compositions are considered. Main factors which determine the efficiency of thin-disperse fillers in the concrete technology are highlighted. It is shown that min- eral micro-fillers for high-strength concretes along with the high rheological activity in plasticized concretes should have hydration activity. A series of x-ray-phase studies for determin- ing the character of influence of modern super-plasticizers on the composition of cement hydration products were conducted. It is shown that super-plasticizers Melflux help to slow down the processes of hydration of silicate phases of cement and stabilization of hydro-aluminate phases. It is established that a thin-disperse carbonate micro-filler contributes to the activation of cement silicate phases. Additives of a new class, viscosity regulators of concrete mixes as well as synthesized nano-metric calcium hydro-silicates performing the role of crystallization centers in the cement stone structure, are attributed to prospective for the use in the technology of concretes of a new generation.

Keywords: high-strength concretes, super-plasticizer, complex additive, mineral filler, ground meal, phase composition, crystallization center, hydration activity, viscosity regulator.

For citation: Kalashnikov V.I., Tarakanov O.V. About the use of complex additives in concretes of a new generation. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 62–67. (In Russian).

S.N. TOLMACHEV, Doctor of Sciences (Engineering) (Tolmach_serg@mail.ru), E.A. BELICHENKO, Candidate of Sciences (Engineering) (Belichenko_khadi@mail.ru), Kharkov National Automobile and Highway University (25, Petrovskogo Street, 61002, Kharkov, Ukraine)

Influence of Entrained Air on Properties of Road Concrete and Fibrous Concrete The article shows the influence of additionally entrained air on the properties of road cement concrete. The results of studies of various authors concerning the the effect of entrained air on the strength of concretes are analyzed. The existing contradictions in them are noted. New experimental results, which show that there are intervals of the content of entrained air, in which the strength of concrete is reduced by 14% per each percent of entrained air, are presented. It is found that the additional air can be engaged in concrete by using air-entraining additives or using polypropylene fibers at that, the pore structure of the concrete depends on the method of air entrainment. It is proved that in the pore structure of concrete with poly- propylene fibers, but without air-entraining additives, smaller pores are present. Their distribution is more uniform, and the strength of the concrete is reduced less than in the case of pores which are formed by an air-entraining agent. This is confirmed by the results of microscopic analysis. Concrete properties are improved in this case. The article gives a theoretical justification of reasons for differences in the pore structure of concrete with fibrous additives.

Keywords: road concrete, fibrous concrete, air entrainment, durability, frost resistance, pore structure.

For citation: Tolmachev S.N., Belichenko E.A. Influence of entrained air on properties of road concrete and fibrous concrete. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 68–72. (In Russian).

T.A. MUKHAMEDIEV, Doctor of Sciences (Engineering) (Takhir50@rambler.ru), A.I. ZVEZDOV, Doctor of Sciences (Engineering) JSC Research Center of Construction (6, 2 nd Institutskaya Street, Moscow, 109428, Russian Federation)

Features of Calculation of Durability of Reinforced Concrete Structures Strengthened with Composite Materials Features of calculating the durability of reinforced concrete structures strengthened with reinforcement elements in the form of canvases, laminates, and meshes from composite materi- als are described. Instructions for calculating the strength of normal cross-sections of flexible and compressed elements by the method of limit forces and according to the deformation model, as well as calculating the strength of oblique sections are presented. Dependences for accounting the features of calculation of reinforced concrete structures strengthened with composite materials are also presented. The comparison of results of the strength calculation of experimental samples of normal sections by the method of limit forces and according to the deformation model with the results of experimental studies is made. The comparison of calculation values of bearing capacity of experimental samples along the oblique section is presented. In total, the processing included about 850 samples which were tested for bending, compression, and action of transverse force. The assessment of the accuracy of proposed calculation methods is made.

Keywords: reinforced concrete structures, reinforcing, composite materials, strengthening, reinforcement, normal section, oblique section, strength calculation.

For citation: Mukhamediev T.A., Zvezdov A.I. Features of calculation of durability of reinforced concrete structures strengthened with composite materials. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 73–77. (In Russian).

G.A. KORABLEVA, Candidate of Sciences (Engineering), S.V. VAVRENYUK, Corresponding Member of RAACS, Doctor of Sciences (Engineering) Far Eastern Research, Design and Technological Institute of Construction, Branch of Federal State Budgetary Institution «Central Research and Design Institute of the Ministry of Construction, Housing and Utilities» of the Russian Federation (14, Borodinskaya Street, Vladivostok, 690033, Russian Federation)

Rock Refuse of Coal Mining with a High Potential Reaction Capability in Light Mortars and Concretes Results of the determination of suitability of waste, thermally changed rock refuse of coal mining with a high potential reaction capability (PRC) for producing a filler of cement light concretes and mortars, by methods of measuring relative deformation of samples according to GOST 8269.0–97 «Crushed Stone and Gravel from Dense Rocks and Waste of Industrial Production for Construction Works. Methods of Physical-Mechanical Tests» are presented. As a filler in mortar bar specimens, a rock of the same color crushed till sand was used in one case, an ordinary mixture selected from the rock refuse (the ratio of fractions according to GOST 8269.0–97) and dissipated at fractions of 0–5, 5–10, 10–20 mm – in another case. To accelerate the appearance of possible corrosion, the samples of mortars (concretes) were hardened in different media and deformations were measured during the long time (up to 710 days).

Keywords: thermal changed rock, rock refuse of coal mining, alkaline corrosion, chemical composition, mineralogical composition, relative deformation, duration of hardening.

For citation: Korableva G.A., Vavrenyuk S.V. Rock refuse of coal mining with a high potential reaction capability in light mortars and concretes. Stroitel’nye Materialy [Construction mate- rials]. 2017. No. 1–2, pp. 78–81. (In Russian).

N.K. ROZENTAL, Doctor of Sciences (Engineering) (rosental08@mail.ru), V.F. STEPANOVA, Doctor of Sciences (Engineering), G.V. CHEKHNY, Candidate of Sciences (Engineering) JSC Research Center of Construction (6, 2 nd Institutskaya Street, Moscow, 109428, Russian Federation)

About Maximum Admissible Content of Chlorides in Concrete A brief review of regulating documents devoted to the maximum admissible content of chlorides in the concrete is presented. The calculation of chlorides quantity in the concrete at the maximum admissible content of chlorides in the initial materials is given. The calculation is made for two compositions of the concrete: with a low and high content of cement. It is shown that the critical content of chlorides, higher of which there is a danger of corrosion, depends on a large number of factors including the content of chlorides, mineralogical com- position of a clinker, content of alkalines, presence of mineral additives, water-cement ratio, conditions of concrete hardening. Due to the difficulty of determining the amount of free chlorides in the concrete, it is proposed to combine the determination of chlorides content with electro-chemical and corrosion tests of steel reinforcement in the concrete.

Keywords: concrete, chlorides, alkaline, mineral additive, depassivation of steel reinforcement, corrosion activity of chlorides.

For citation: Rozental N.K., Stepanova V.F., Chekhny G.V. About maximum admissible content of chlorides in concrete. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 82–85. (In Russian).

V.N. VERNIGOROVA, Doctor of Sciences (Chemistry), S.M. SADENKO, Candidate of Sciences (Engineering) (sadenko@mail.ru) Penza State University of Architecture and Civil Engineering (28, Germana Titova Street, Penza, 440028, Russian Federation) About Nonstationarity of Physical-Chemical Processes Occurring in Concrete Mix Characteristics of a concrete mix and its sub-system СаО–SiO2–H2O are presented. Adsorption heats and the affinity of main intermediate particles Н+, ОН – , H o и OH o to the electron are given. The mechanism of interaction of CaO with water and reasons for multivalency of the calcium atom are shown. Calcium hydrosilicates as solid solutions of the introduction of CaO and H2O into the gel of the polysiliсic acid SiО2 . nН2О with wide spheres of homogeneity are considered. Experimental data on the kinetics of calcium cations uptake by the polysilicic acid and the kinetics of SiО2 dissilution are presented. Self-oscillations of these processes have been established with addition of LST. The subsystem СаО–SiO2–H2O and the concrete mix are polystationary. Self-oscillations of concentrations of СаО и SiO2 in the liquid phase of the subsystem СаО–SiO2–H2O indicate the non-stationary, non-linear character of these processes. Chemical processes of the interaction of minerals β-C2S and C3S with water with formation of calcium hydro-silicates are necessary to analyze not from the positions of classical chemical kinetics but with the method of computer mathematical simulation

Keywords: nonstationarity, concrete mix, calcium hydrosilicates, intermediate particles, self-oscillations of concentrations, polystationarity, computer mathematical simulation.

For citation: Vernigorova V.N., Sadenko S.M. About nonstationarity of physical-chemical processes occurring in concrete mix. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 86–89. (In Russian).

M.K. KABANOVA1, Candidate of Sciences (Engineering), S.A. TOKAREVA1, Director (keramzit_union@mail.ru); P.P. UVAROV2, Counselor
1 AO «KERAMZIT» (3a, Eroshevskogo Street, 443086, Samara, Russian Federation)
2 Russian Academy of Engineering (9, bldg. 4, Gazetny Pereulok, Moscow, Russian Federation, 125009

Main Criteria are Safety, Ecological Compatibility and Durability of Building Materials Examples of negative experience in the use of non-tested heat insulation materials harmful to health and life of people, thermal protection of buildings are presented. The lag and short- comings of technical regulation in the construction industry, in the development and approval of technical rules for safety of building materials and products are indicated. It is proposed to develop the state technical policy aimed at producing safe and ecological building materials, especially durable, energy efficient, fire safe, ecologically clean, affordable and operationally reliable expanded clay and expanded clay products and structures on its base. Present problems of safety and ecology of housing should be solved complexly and systematically on the science base. The construction of safe and environmentally friendly housing should be an integral part of the complex state program of people preservation of Russia.

Keywords: housing construction, safety of buildings, eco-friendly materials, technical regulation in construction complex, heat protection of buildings, expanded clay, expanded clay- concrete products.

For citation: Kabanova M.K., Tokareva S.A., Uvarov P.P. Main criteria are safety, ecological compatibility and durability of building materials. Stroitel’nye Materialy [Construction materi- als]. 2017. No. 1–2, pp. 90–93. (In Russian).

A.A. KUSTOV, Engineer (alexeykustov@outlook.com), A.M. IBRAGIMOV, Doctor of Sciences (Engineering) (Igasu_alex@mail.ru) National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

Mathematical Models of Technical Fabrics with Coating Recently, the interest in soft shell structures increased again. The material from which these structures are made is a technical fabric with coating. An important aspect, when designing soft shell structures, is the study of the behavior of technical fabrics with coating under various external impacts. The article presents the most distributed mathematical (numerical) models of the material verified with field tests. Usually, they are divided into two main groups taking into account the geometric and physical non-linearity separately which are typical for technical coated fabrics. Mainly, the emphasis in the work is placed on foreign models, due to the small number of domestic developments in the field of mathematical (numerical) models of the material.

Keywords: technical fabric with coating, numerical simulation, soft shell structures.

For citation: Kustov A.A., Ibragimov A.M. Mathematical models of technical fabrics with coating. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 94–98. (In Russian).

V.G. KUZNETSOV 1 , President, General Director (ppfp_astiki@mail.ru); N.N. KISELEV 2 , Doctor of Sciences (Engineering), Head of Branch Research Laboratory of Powerful Excavators, Laureate of Lenin and USSR State Prizes, E.V. KOCHETOV 2 , Candidate of Sciences (Engineering) , (sdm@mgsu.ru); I.P. KUZNETSOV 1 , Commercial Director (astik_kp@mail.ru).
1 OOO «As-Tik KP» (16, Teterinsky pereulok, 109004, Moscow. Russian Federation)
2 Moscow State University of Civil Engineering (26, Yaroslavskoye Highway, 129337, Moscow, Russian Federation) Reducing the Influence of Stickiness of Rocks and Raw Materials on Working Efficiency of Equipment Due To Application of PPFP-Astiki An important property of moistened clay soils is their stickiness, their ability to stick to surfaces which contact with them in the process of earthwork and following transportation. Quantitative values of stickiness of excavated soils are in a wide range (from 0.5 to 50 KPa and more). It is noted that the volume of stuck rock in excavator buckets is 15–35% of their estimated capacity, discharge capacity of bunkers is reduced by 20–50%, load capacity of a dump truck is reduced by 16–22%, dump cars – by 15–20%. The use of anti-sticking plates PPFP-Astiki makes it possible to significantly reduce (up to 2 KPa) and often completely eliminate the stickiness of moistened rocks and raw materials, its impact on the discharge capacity of lifters and bunkers by 1.4–1.8 times, performance of excavator equipment by 12%, load capacity of dump trucks and dump cars by 15–18%. Simultaneously, the heavy physical work which is used, as a rule, for cleaning of stuck devices of equipment is liquidated.

Keywords: anti-sticking plates, rocks, raw materials, stickiness, working capacity, PPFP-Astiki.

For citation: Kuznetsov V.G., Kiselev N.N., Kochetov E.V., Kuznetsov I.P. Reducing the influence of stickiness of rocks and raw materials on working efficiency of equipment due to appli- cation of PPFP-Astiki. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 99–103. (In Russian).

N.I. KOZHUKHOVA, Candidate of Sciences (Engineering) (kozhuhovanata@yandex.ru), D.N. DANAKIN, Engineer (danakin93@mail.ru), I.V. ZHERNOVSKY, Candidate of Sciences (Geology and Mineralogy) (zhernovsky.igor@mail.ru) Belgorod State Technological University named after V.G. Shukhov (46, Kostyukov Street, Belgorod, 308012, Russian Federation)

Features of Producing Geopolymeric Gas Concrete on the Basis of Fly Ash of Novotroitskaya TPS* Issues of producing energy-efficient, environmentally friendly and affordable building materials with the use of large-tonnage industrial waste do not lose their relevance. Within the frame of this research, one of the weakly demanded industrial waste, fly ash of the Novotroitskaya Thermal Power Station of acidic composition with a low hydraulic activity as a main component when producing cellular composites on the basis of a geopolymeric binder, has been studied. On the basis of experimental-analytical studies, the suitability of the fly ash considered as a reaction-active component as a result of its alkaline activation when producing the geopolymeric binder has been established. Compositions of the geopolymericas con- crete with low indexes of density and heat conductivity have been developed. The reasonability and perspectivity of producing efficient gas concrete composites on the basis of the geo- polymeric binder with the use of fly ash of TPS of acidic composition has been substantiated.

Keywords: fly ash, geopolymaric gas concrete, energy efficiency, industrial waste.

For citation: Kozhukhova N.I., Danakin D.N., Zhernovsky I.V. Features of producing geopolymeric gas concrete on the basis of fly ash of novotroitskaya tps. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 113–117. (In Russian).

E.V. KOROLEV, Doctor of Sciences (Engineering) (korolev@nocnt.ru), A.N. GRISHINA, Candidate of Sciences (Engineering) (grishinaAN@mgsu.ru), A.P. PUSTOVGAR, Candidate of Sciences (Engineering) National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

Surface Tension in Structure Formation of Materials. Significance, Calculation, and Application Surface tension, the most important thermodynamic value influencing on many physical-chemical processes occurring in the substance – from a critical nucleus at homogeneous nucle- ation to capillary phenomena at water absorption by a porous-capillary body – is considered. The size dependence of surface tension establishing its reduction with decreasing particle sizes has been studied. It is shown that the surface tension most significantly influences at the stage of early structure formation of a composite substance in the course of aggregation of structural elements of the substance in structures of a higher hierarchical level, at the presence of surfactants with a high level of lateral interaction especially. Experimental research in this direction will make it possible to answer very important material science issues for current building composites, namely the dominant role of defect sizes, rational directions of application of nano-technology methods as well as to reveal the rational groups of modifiers for controlling parameters of the structure and properties of building composites.

Keywords: surface tension, dispersion, surface energy, defects, structure formation.

For citation: Korolev E.V., Grishina A.N., Pustovgar A.P. Surface tension in structure formation of materials. significance, calculation, and application. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 104–108. (In Russian).

A.A. PAK, Candidate of Sciences (Engineering) (pak@chemy.kolasc.net.ru), R.N. SUKHORUKOVA, researcher The I.V. Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials of the Russian Academy of Sciences Kola Science Center (26a, «Academic Town», Apatity, 184209, Murmansk region, Russian Federation)

Features of Technology of Gas Concrete Products and Proposals for Its Enhancement An analysis of the traditional technology of gas-concrete products is presented, its distinctive features and shortcomings are noticed. Proposals for the elimination of noticed shortcomings are formulated: to add cold water to a gas-concrete mix, produce the products in the closed moulds and begin the thermal-humidity treatment of products without preliminary curing. Due to the full compression of concrete by rigid walls of the mould, it is possible to implement the accelerated temperature raise in the heating aggregate without fear of destructive destruc- tions of concrete. Experiments conducted found that to obtain the concrete of improved strength, it is necessary to ensure the effect of pre-pressing of the gas-concrete mix (internal stress) in the closed mould. For this, it is recommended to form the products from gas-concrete mix with calculated density for a mark lesser (100 kg/m 3) in the closed mould than in the open mould under the condition that equal quantities of concrete mix are filled in both moulds.

Keywords: gas concrete, technology, strength, open and closed mould.

For citation: Pak A.A., Sukhorukova R.N. Features of technology of gas concrete products and proposals for its enhancement. Stroitel’nye Materialy [Construction materials]. 2017. No. 1–2, pp. 110–112. (In Russian).

22–25 ноября 2016 г. на базе Петербургского государственного университета путей сообщения императора Алек сандра I (ПГУПС) при поддержке Министерства транспорта Российской Федерации, Федерального агентства же лезнодорожного транспорта, ОАО «Российские железные дороги» состоялась Международная научно-практическая конференция «Строительные материалы, конструкции и сооружения XXI века», посвященная 100-летию профессора О.В. Кунцевича. Информационным партнером конференции выступил журнал «Строительные материалы»®. Участие в конференции приняли ученые и специалисты из России, а также Германии, Испании, Румынии, Польши, Литвы и др.