Table of contents
G.R. BUTKEVICH, Candidate of Technical Sciences, FGUP “VNIPIIstromsyrie” (Moscow)
Data on the development of non-metallic building materials industry in Russia and the USA during several decades are analyzed. Information about the changes in production volumes, productivity of labour, prices, use of natural resources is presented. Analogies of development of the industry and major differences are revealed.
Key words: non-metallic building materials, sand-ravel mix, productivity of labour, prices.
V.I. KALASHNIKOV, Doctor of Technical Sciences, D.M. VALIEV, engineer, D.V. KALASHNIKOV, Candidate of Technical Sciences, the Penza State University of Architecture and Civil Engineering; N.V. MASLOVA, Candidate of Technical Sciences, the Togliatti State University (Samara Oblast)
The practice of using the ultra-high-strength concrete and fibrous concrete in Russia and abroad is considered. Conditions required for producing the efficient concrete are formulated. The role of heat treatment in achieving the high durability is considered.
Keywords: high-strength concrete, microtechnology, micronanotechnology, powder activation, quality criteria, heat treatment.
N.N. CHERNOUSOV, R.N. CHERNOUSOV, Candidates of Technical Sciences, A.V. SUKHANOV, engineer, the Lipetsk State Technical University
The study of prototypes of concrete in the form of eights that were tested in the specially designed device which made it possible to determine the modulus of elasticity at tension and exercise the quasi-static loading has been conducted. A new dependence for description of fine concrete operation in the course of axial compression has been obtained; applicability of Sarzhin and Karpenko formulas for describing the stress-deformation curve at axial tension is confirmed.
Keywords: fine sand concrete, modulus of elasticity, axial tension and compression, analytical dependences.
I.M. BARANOV, Candidate of Technical Sciences, OOO “NTTS EMIT” (Moscow)
The sequence of work with the static viscosimeter for determining rheological characteristics of high-plastic concrete mixes as well as desired values of these characteristics for concrete of underwater concreting are presented.
Key words: rheology, special concretes, underwater concreting.
A.P. PICHUGIN, Doctor of Technical Sciences, V.V. BANUL (email@example.com), M.O. BATIN (firstname.lastname@example.org), engineers, the Novosibirsk State Agrarian University
Results of the study of thermally sprayed polymeric coverings made of low-pressure polyethylene for metallic surfaces to ensure the anticorrosion protection of steel elements of treatment facilities of livestock complexes are presented. The active influence of nanosize components on the formation of a covering structure, improvement of adhesion, reduction of shrinkage of polyethylene sprayed coverings, improvement of plastic and operation properties are revealed.
Keywords: treatment facilities, corrosion of metal, polymeric protective films, spraying, siliceous, carbon nanotubes UNT, preliminary treatment with nanosize compositions, improvement of corrosion and operation durability.
Yu.E. VASILIEV, Doctor of Technical Sciences, the Moscow State Automobile and Road Technical University (MADI); A.V. KOCHETKOV, Doctor of Technical Sciences, the Perm National Research Polytechnic University; I.Yu. SARYCHEV, engineer (email@example.com), the Yuri Gagarin State Technical University of Saratov; S.Yu. ANDRONOV, Director, PUITS “VOLGODORTRANS”
The technology of production of oil road bitumen is analyzed. It is shown, that the existing methodology of assessment of bitumen quality at the asphalt concrete factory does not guarantee the reliable information on material quality. The cause of it is the methods of bitumen testing regulated by effective normative documents that leads to significant delay of information on material properties regarding the real technological process. The nonconformity of the practice of using normative documents regulating the methods of control over quality of oil road bitumens to processes of its changes at all stages of its life cycle is noted. It is shown, that for solution of the problem of road construction quality it is necessary to develop and introduce into the practice the rapid test methods that ensure the acquisition of reliable information on the quality of bitumen and asphalt-concrete mixes in real-time mode.
Keywords: bitumen, oil economy, oxidation, dispersion of indices, technical standardization, motor roads.
A.N. SAVELIEV, engineer (firstname.lastname@example.org), the Perm National Research Polytechnic University
Problems of the improvement of operational qualities of the stone mastic asphalt concrete (SMAC) mixes by introducing various complex additives into them are considered. The composition of a complex additive to SMAC with the use of a modifier, previously dissolved in the settled tar of wood pyrolysis has been developed. An analysis of the dependence of physical and mechanical characteristics of SMAC on the type of modifier in the composition of complex additive is presented. The research conducted show the effectiveness of the application of complex additives on the basis of cellulose fibers in a composition with a solution of rubber-like polymers in the settled tar of wood pyrolysis. The estimation of influence of additives on the properties of SMAC is made.
Keywords: stone mastic asphalt concrete, solution of polymers, stabilizing additive, cellulose fiber, bitumen.
P.S. BELYAEV, Doctor of Technical Sciences, O.G. MALIKOV, Candidate of Technical Sciences, S.A. MERKULOV, undergraduate (email@example.com), D.L. POLUSHKIN, Candidate of Technical Sciences, V.A. FROLOV, undergraduate (firstname.lastname@example.org), the Tambov State Technical University
Problems of increasing the quality of road binders by means of modification of road oil bitumen with thermoplastics and rubber technical goods waste are considered. The results presented confirm the possibility of reducing the cost of the modified road binder and perspective of the utilization task of large-tonnage polymeric waste which are result of production of building materials.
Keywords: bitumen modification, polymer bitumen binder, polymer waste.
A.A. LUKASH (email@example.com), G.V. GLOTOV, T.I. GLOTOVA, Candidates of Technical Sciences, the Bryansk State Engineering-Technological Academy
The mechanism of appearance of elastic and residual deformations in the relief plywood arising in the process of its glueing is considered. Conditions under which the relief plywood loses its shape and delaminates have been determined. It is established that the relief plywood which operates in dry heated premises for a long time maintains its sizes and shape.
Keywords: relief, plywood, glueing, operation, timber, deformation, mould, damping
A.G. PEREKHOZHENTSEV, Doctor of Technical Sciences, the Volgograd State University of Architecture and Civil Engineering
Methods of the calculation of a coefficient of moisture diffusion depending on changes of temperature and moisture content of porous materials are considered.
Keywords: wet porous materials, coefficients of hydraulic conductivity.
I.Ya. GNIP, S.I. VAYTKUS, S.A. VEYALIS, Yu.S. VALIVONIS, Candidates of Technical Sciences, the Vilnius Gediminas Technical University (Lithuania)
Results of the experimental study of creeping deformations of polystyrene foam products of EPS 80, EPS 120 и EPS 150 types under the permanent compressive stress acting perpendicularly to the surface of products are presented. Mathematical models of optimization of the thickness of square polystyrene samples with a side equal to 100 mm have been obtained by using the method of statistical planning of creeping. The graphic interpretation of the models obtained is presented. Relative creeping deformations for polystyrene foam EPS 80, EPS 120 и EPS 150 have been determined on the basis of the direct experiment of tn=122 days duration at the permanent compressing stress σс=0,35 σ10%. Residual deformation εз (plastic proper) when removing the constant unit load σс at time tn has been defined. Predictive values of creep deformation εс(T=10 years) for forestalling of 10 years are presented.
Keywords: polystyrene foam, protracted compression, statistical planning of experiment, creeping flexibility, creeping deformation, prediction, optimal thickness of samples.
V.B. BABAEV, engineer, V.V. NELYUBOVA, Candidate of Technical Sciences, I.V. ZHERNOVSKY, Candidate of Geological-Mineralogical Sciences, the Belgorod State Technological University named after V.G. Shukhov
The actuality of developing methods of modification of basalt fiber for improving the efficiency of its use in cement concretes of various functional purposes is substantiated. Methods of thermal treatment of fiber have been developed. To study the alkali resistance of fiber the experimental simulation of natural processes taking place during the hydration of cement stone in connection with the processes of changing the microstructure of the fiber surface is proposed. On the basis of the analysis of changing the microstructure of fiber surface, active centers, phase composition according to data of IR-spectroscopy and X-ray fluorescence analysis of fiber before and after the thermal treatment, the phenomenological model of the process of modification of basalt fiber surface in the course of thermal treatment is proposed.
Keywords: basalt fiber, fiber, thermal treatment, alkali resistance, model
D.S. TOLMACHEV, engineer (Tolmach_serg@mail.ru), the Kharkiv National University of Civil Engineering and Architecture (Ukraine)
Issues of the influence of shrinkage on the strength of concrete are considered. It is shown that with increasing the weight of cement in the mortar composition the shrinkage is composed of air and contraction components and its value increases because of contraction. It is established that the decrease in concrete activity leads to bigger increase in shrinkage deformation than the reduction of sand fineness. The introduction of a microfiller of metakaolin type into the composition of mortars leads to reducing their shrinkage and formation of more compact structure.
Keywords: durability, strength, concrete shrinkage, cement mortar, deformation, structure, metakaolin.
S.V. KOTOV, engineer (firstname.lastname@example.org), S.P. SIVKOV, Candidate of Technical Sciences, the D. Mendeleyev University of Chemical Technology of Russia (Moscow)
It is shown that an efficient intensifier of grinding should be multi-component and contains the substances with different mechanisms of action in the course of material grinding. It is established that salt-electrolytes and multi-component intensifiers of grinding on the basis of these salts are efficient intensifiers of grinding of supplementary cements. The study of specific surface, distribution of sizes of particles, total heat release of the Portland cement grinded has been conducted; the strength of cement stone samples for the Portland cement studied has been defined.
Keywords: intensifiers of grinding, Portland cement with addition of limestone.