The methods for determining the standards for the preventive maintenance system and repair are analyzed, it is found that the current norms are essentially outdated and require revision at the federal level. It is shown that the specifications for maintenance and repair specified by the operating time for modern cars should be revised in favor of standards determined by their condition, which will allow the introduction of individual standards for each car, taking into account the operating conditions and its technical condition.
Keywords: Strategy, method, standard, parameter, maintenance, repair, maintainability, mileage, reliability, operation
The problem of selection of diagnostic signs is solved by methods of statistical, spectral and entroic processing of signals and the logical analysis of their results. Results of data processing allowed to choose the most efficient characteristics (diagnostic signs) of signals providing separability of signals in the chosen priznakovy space i.e. classification. The problem of algorithmization of diagnostics of electrodrive fittings (further EPA) is solved as a problem of a pattern recognition of five classes of a condition of EPA on the basis of comparison of the current Boolean combinations to seven standards.
Keywords: electrodrive fittings, spectral analysis, entropy of Shannon, permutation entropy, basic vector, pattern recognition
The article considers the topicality of the development of cement foam concrete meeting modern requirements for energy saving and energy efficiency. The interrelation of physical and mechanical properties of cement foam concrete with the features of its structure formation at macro- and microlevel is considered. The main components for the manufacture of structural and heat-insulating cement foam concrete are described. The results of experiments on the determination of the dependence of the parameters of the structure of a foam concrete mixture, which form the physical and mechanical properties of finished products, are presented. A mechanism has been established for the active participation of particles of fibrous cellulose filler in the organization of the structure of a foam concrete mix and samples based on it. The optimal concentration of fibrous cellulose filler in the raw meal mix was confirmed.
Keywords: structural and heat-insulating foam concrete, modifying additives, technical carbon, fibrous filler
In the scientific article, the problem of instrumental and methodological support of works on a special assessment of working conditions is considered. The paper presents an approach to the selection of measuring equipment for the measurement of harmful production factors, which is based on the method of expert assessments. The results of studies of the application of the expert method for determining the possibility of using a group of instruments for the assessment of physical and chemical factors for conducting a special assessment of working conditions at workplaces of a machine building enterprise are presented. Recommendations are presented for equipping the laboratory with laboratories that carry out special assessment work in the conditions of machine building enterprises.
Keywords: labor protection, instrumentation, measuring equipment, special assessment of working conditions, method of expert evaluation
In this paper, the temperature distribution from a point source of heat under convective heat transfer is studied. The Navier-Stokes equation describing the steady two-dimensional laminar motion of a fluid is solved numerically. The distribution of the temperature field of a heat-loaded point source is obtained under appropriate boundary conditions, supplemented by the boundary conditions for the flow velocity to equal zero on the paraboloid walls by numerical integration using the control volume method.
Keywords: Radiator protrusion shape, thermal conductivity, thermal apparatus mode, the temperature of the heat source
This article deals with the field of application of fiber-reinforced concrete, reveals the advantage of using fiber-reinforced concrete in comparison with conventional concrete. The efficiency analysis of the use of fiber-reinforced concrete is analyzed.
Keywords: fiber concrete, concrete, reinforced concrete, structures, technologies, installation, fiberglass concrete, reinforced concrete structures, tension, prestress, basalt fiber concrete
Interference of mineral fillers, phosphor and chloride contained plasticizes, bromine contained fireproofing compounds and ferrocene derivatives to thermal stability, ignitability and smoking capability of epoxy composite materials was under consideration. The authors have eliminated that the phosphate plasticizes do not affect practically to epoxy polymers' combustibility, but to reduce smoking capability of composites. Different types of mineral fillers by concentration less then 45% by mass do insignificantly affect ignitability of epoxy composites. Different types of aromatic bromine contained additive fireproofing compounds do not affect to combustibility of such composites. The ferrocene derivatives surpass the ferrocene by effectiveness of smoke redesign. Correlation of the oxygen index with limiting oxygen concentration, heat of burring and critical density of heat flow graph was shown up. The main service properties and the data of inflammability of original patented composites are presented.
Keywords: bromine contained fireproofing compound; ignitability; combustibility; smoke ability; composites; fillers; plasticizes; ferrocene derivatives; epoxy oligomers
The technology of the new generation is an injection method of polymer waterproofing. As for polymeric compositions for injection are used polyurethane compositions; materials based on epoxy tar; micro cement; acrylate gels. Acrylate gels can provide the necessary reliable, highly elastic barrier from water pressure. Reducing the cost of injection waterproofing is possible through the use of acrylate waste paintwork materials (PWM). The results of studies on the use of acrylate wastes (PWM) as a water-repellent additive to concrete, allow us to recommend identical wastes as materials for volumetric water-repellent treatment of building structures in order to reduce the cost of water resistance by injection.
Keywords: injectable waterproofing for buildings and constructions, waterproofing materials, paintwork materials, polymer wastes
The peculiarities of the activity of mobile car repair shops are considered. Mathematical models for determining indicators, taking into account the randomness of the receipt of requirements for maintenance and the duration of the services themselves, are proposed.
Keywords: mobile car repair shop, probability, criteria, complex indicator, efficiency
The use of sunflower husk waste allows to solve the problem of utilization of agricultural waste and obtaining adsorbents for wastewater treatment of industrial production from ions of heavy metals, in particular copper. Studies on the evaluation of the adsorption capacity of materials have been carried out and choose the optimal method of manufacturing the sorbent.
Keywords: husks of sunflower, vegetable adsorbents, waste water, heavy metal ions, melanin
The problem of determining the environmental hazard in the development and disposal of oil contaminated soil at the time of construction of buildings and structures is very relevant, especially for sites on which previously located industrial zones with different production. Unfortunately, at the moment, there is no clear understanding of the MPC of petroleum products in the ground. Various inspection inspections and specialized landfills treat the degree of soil contamination with oil products in different ways. In this regard, there is a danger of incorrect definition of the hazard class of the soil, which can lead to subsequent pollution of the environment.
Keywords: soil, oil product, hazard class, resolution, pdk, range, ecological condition, soil utilization, construction, concentration, pollution
From the pilot section of the gas pipeline, after ten years of operation, specimen-witnesses were seized. The gas pipeline consists of reinforced polyethylene pipes with an average adhesive reinforcing layer. The results of mechanical tests of model samples are given in the article. Investigations of the deformation-strength properties of the witness specimens show a decrease in the temperature of the viscous-brittle transition to -15 ° C. These results indicate a deterioration in the adhesion between the outer layers of PE80 and the middle technological layer. Good adhesion led to the emergence and development of a fragile crack. Stability tests at constant pressure showed satisfactory results, not a single sample collapsed. According to the research data, the reinforced polyethylene pipe did not deteriorate its deformation-strength properties for ten years of operation of the gas pipeline under pressure.
Keywords: Reinforced polyethylene pipe, specimen-witnesses, adhesion, stretching, viscous-brittle transition, resistance at constant internal pressure
Covers the relevant issues of reduction of construction period by using prefabricated structures. The proposed method is confirmed by calculations proving its reliability and feasibility. When developing the method was considered economic component of the design and construction of industrial complexes
Keywords: organization of construction; modular construction, industrial construction
The methods of directed formation of the variational structure of concrete products and structures are considered in the article. The experience of Russian scientists in the issues of obtaining articles of different density over the section has been studied. The problems of the technology of obtaining articles of different density along the section are considered, the main principles of shaping the variational pore structure of aerated concrete for monolithic enclosing structures, the optimal schemes for forming two-layer wall products from concrete of various densities, forming a structure with a double skeleton - mineral and polymeric - by sintering the polystyrene grains, the formation of variational structure of magnesian foam concrete, which involves sequential laying of foam masses with various average, perspectivity of the use of reinforced concrete constructions of a variational structure.
Keywords: Variational structure, concrete products and structures, reinforced concrete, aerated concrete, foam concrete, expanded clay concrete, density, fire resistance
The soils of the territories adjacent to the city of Rostov-on-Don are studied, characterized by a highly developed transport system. Agricultural land adjacent to the highway is often closed by forest strips. But, large areas of land are not protected by forest strips. A lot of lead accumulates in the soil of open agrocenoses. It is necessary to create forest belts around new highways
Keywords: soil, iead, mobile forms, gross content, forest melioration