Blasting operations are often the only way to prepare the material for the recess for laying roads and railways in the rocks. Explosive loosening is also used to extract stone as a building material. Field testing is costly and often dangerous. Therefore, it is necessary to first conduct a series of experiments on the model and find out the conditions for ensuring good quality loosening of rocks. In order for the results of model tests to be transferred to nature, a similarity between model and specimen is required. The approximate similarity is achieved by the equality of the similarity criteria for the model and specimen. The characteristic similarity criteria are obtained by analyzing the physical quantities inherent in a mechanical system using the theory of dimension and similarity. The received criteria are presented in the classical form. These are the criteria of Strouhal, Froude, Cauchy and Newton.

Keywords: explosive loosening, rock material, deceleration interval, similarity criterion, modeling, rock density, model, specimen, expansion height, dimensionality, physical quantity

This paper reports on the results obtained on the diagnostics of a steam pipeline of a thermal power plant; it analyzes the effect of thermal fatigue on the structure and properties of the 12Kh1MF steel and possible reasons for the emergency destruction of steam pipeline elements before the exhaustion of economic life. Ultrasonic testing and additional heat treatment are proposed to be used for the detection and elimination of structural inhomogeneity in the metal. The applicability of statistical technique to analyzing data on the loading history of a steam pipeline is studied, which enables us to evaluate the damaging effects of loading cycles and to develop a plan of preventive measures, as well as to increase the accuracy of predicting the residual life of steam pipeline elements.

Keywords: metallic structure, diagnostics, degradation, steam pipeline, thermal fatigue, microstructure, mechanical properties, residual life

The results of theoretical research and analysis of methods that will significantly reduce the weight of the gravity oil platform are presented. At the same time, its static, dynamic, and shear stability will remain under the influence of wind, wave, ice load and current load. In order to reduce the weight and overall dimensions, it is proposed to outline the lower part of the platform base with a metal sheet pile wall. As a result of theoretical studies, the dependence of the shear force under the influence of external forces acting on the platform during operation on the physical and mechanical properties of the soil and the size of the sheet pile wall is found, which will significantly reduce the weight of the platform and the cost of its construction.

Keywords: gravity oil platform, shear stability, tongue-and-groove wall, external forces acting on the platform, rollover stability

The article describes the main stages of development of the construction of green roofs in Russia and abroad, the basic scheme and the technology of green roofs.

Keywords: Green construction, green roofing, environmental certification, noise pollution, drainag

The article presents the results of experimental studies of microclimate parameters (temperature, intensity of thermal radiation) at the area of an arc steelmaking furnace, on the basis of which the adequacy of mathematical models of heat transfer implemented in the ANSYS software package is confirmed. Mathematical models of heat transfer are represented by the discrete ordinate model (DO), which most accurately describes the transfer of radiative heat in space, and the Shear Stress Transport (SST) turbulence model. The use of these mathematical models will make it possible to pre-evaluate the thermal radiation situation at the projected or reconstructed objects, and also will allow you to choose effective means of thermal protection in advance.

Keywords: arc steelmaking furnace, mathematical models, experimental studies, heat transfer, temperature, intensity of thermal irradiation

The paper studies the applicability ofthe coercive force (Нс) as a parameter for measuringthe wall thickness ofpipelines,vessels,andother metallic structuresthroughnonmagnetic insulationduring material degradation undercorrosion conditions. A procedure is developedfor remote inspectionof metallic structures atsites of maximum corrosion rateby the coercimetricmethod,withoutbreaking the insulationandstopping the operation ofthe object being tested.The effects of metal thickness, the size ofthe poles of the magnetizer, andthe thickness of non-ferromagneticinsulationon the absoluteand relativevalues of the coercive force are comparatively analyzed. The application of theproposed relative value methodis shown to be able to decrease significantlythe effectof steel composition and structureonthe metal thickness dependence of Нс. The results of measuring the coercive force of differently thick 09G2S steel specimens through non magnetic insulation are presented, as well as the behavior of the relative values of the coercive forceas dependent onmetal and insulation thickness.Foridentical metal thicknesses, the absolute values of the coercive force of different steels may differby a factor of 10 ormore, whereasthe difference in the relative values of Нс with equally decreasing metal thickness does not exceed 15%. The developedtechnique isinsensitivetothe misalignment of the outer and innermetal surfaces,and itenablesthe thickness oflow-alloysteels like 09G2Sto be measured witha relative error of 10%.

Keywords: metallic structure, diagnostics, degradation, corrosion, coercive force, thickness measurement, nonmagnetic insulation

The article considered the propagation of a long impulse signal in a hydroacoustic waveguide. A solution is given for a replica of a impulse signal in the second approximation of the dispersion theory. The propagation of a single-mode and multimode impulse in a Pekeris waveguide with a bottom in the form of an absorbing half-space is simulated. The acoustic properties of the half-space correspond to medium sand with an average grain size 0,3 mm. The result of the solution in the second approximation of the dispersion theory is compared with the result of the simulation of the impulse replica obtained as a convolution of the input signal with the impulse response of the waveguide. The disadvantages of the solution in the second approximation of the dispersion theory are shown and analyzed. It is shown that the theory of dispersion incorrectly reproduces the transients when the signal is switched on and off in cases where the signal frequency lies near the critical frequency of the first or second mode. It is shown that the theory of dispersion correctly reproduces the envelope of a multimode impulse signal.

Keywords: impulse signal, normal modes, group velocity, dispersion theory, intramode dispersion, intermode dispersion

The article contains an analysis of the design and calculation process in the 3d system NX Siemens oil and gas facilities. Research methodology - analysis of scientific literature on a given problem, as well as practical domestic experience. Creation of a 3D model of an oil and gas structure, with the possibility of changing the construction parameters at the design stage. Detailed analysis of the model, which allows you to describe in detail the stages of construction of the structure and selection for each stage of construction of specific equipment and materials. Engineering analysis modules are built into the software solution, built-in solvers are designed to calculate the different operation scenarios of the structures being developed, which make it possible to approach the real conditions of operation of the designed structure. The relevance of the use of the NX Siemens system is due to the complexity of the design of oil and gas structures and the influence of all parameters of the materials and technologies used on the performance indicators during the operation of the oil and gas structure. The same software solution allows you to prepare a complete package of design and technological documentation, prepare tasks for processing parts and materials, and ensure quality control during their manufacture.

Keywords: design, calculations, oil and gas facilities, companies, objects,

The analysis of the functional purpose of high-rise buildings in Russia and abroad is presented. The dynamics of the growth of construction of ultra-tall buildings for the period 2000-2020 is considered. The trend towards the use of composite materials in the construction of ultra-high buildings is revealed. The dynamics of growth of construction of high-rise buildings in Russia is considered. Revealed changes in the functional purpose of high-rise buildings in Russia on the example of the tallest buildings in the Russian Federation. Changes in the use of construction technologies and materials in the construction of high-rise buildings and their impact on the quality of buildings under construction are presented.

Keywords: high-rise buildings, construction, building materials

A methodology for building an optimal enterprise architecture was developed to improve the efficiency of using information technologies in the digital industry, aimed at providing information support for production systems using modern integrated information technologies. The architecture is decomposed into a number of representations, which are chosen as invariant aspects determined by the analysis of various models of enterprise architecture. We propose to design of an information support subsystem for development of digital industry enterprise promising architecture as a practical tool. Its elements are formed in the field of information technology as a result, and a comprehensive indicator of the effectiveness of a given enterprise architecture is calculated. The modeled subsystem includes a module for storing and managing enterprise architecture elements, a module for storing and managing enterprise architecture selection criteria, a module for creating a promising enterprise architecture based on the implementation of its modeling algorithms, and a module for generating reports. The subsystem will enable the company to create the conditions for efficient creation and exploration of new types of scientific and technical products, timely to market these products, in particular, to ensure the export potential and import substitution and will reduce the duration of the production cycle, improve the effectiveness of in-service process equipment.

Keywords: enterprise architecture, digital industry, optimal enterprise architecture, information support subsystem

Recently, the issues of improving the environmental situation in the urban environment have become more relevant than ever. "Green architecture" gets popularity not only in Russia but over the world as well. The necessity of this type of architecture causes the need to improve air quality and environmental factors of urban conditions. Most often, greening the roof of a building or greening the facades is used for ecologization, so-called the element of wall greening and also greening of vertical surfaces of buildings (phyto facade).

Keywords: green architecture, vertical greening, green wall, waving plants, green screens, phyto facades

The problem of experimental determination of the parameters of the error model of MEMS accelerometers is considered. Possible sources of errors and their nature are shown. When developing a model of errors, the influence of non-orthogonality of the axes, temperature dependences of the conversion coefficient, and displacement of zeros were taken into account. A mathematical model of the MEMS accelerometer errors and an algorithm for the experimental determination of its parameters have been developed. Specific structural schemes of the stands are presented. Their hardware and software implementation is described. Specific features of temperature control in a small-sized heat chamber with a heater and a cooler based on a Peltier element are considered. An example of experimental estimation of the parameters of the error model for one axis of the MPU6050 accelerometer is shown. The developed tools make it possible to start a systematic study and objective comparison of the characteristics of MEMS accelerometers from different companies, as well as to obtain their working error models suitable for use in filtering algorithms in the construction of various systems of inertial navigation and angular stabilization of objects.

Keywords: microelectromechanical systems, MEMS, errors, models, methods, designs, accelerometer, microcircuit, modeling

An auxiliary subsystem of a multi-agent robotic sowing system for agricultural crops, including autonomous robots functioning as part of a group, is considered as an object of research. The aim of the study is to improve the management of adaptability and productivity of agricultural plants. The tasks of the study included the development of the simplest autonomous robot for introducing working fluids into the cenosis and the choice of its parameters. The experimental data were processed by the methods of mathematical statistics. The developed autonomous robot is made of polymer gel and has the properties of a quasi-liquid body. Its parameters are determined, presented experimentally certain mathematical dependences of the interaction of autonomous robots with working fluids, for example, rainwater.

Keywords: seeding, watering, robotic subsystem, autonomous robot, polymer hydrogel, quasi-liquid body

This work analyzes the methods of dismantling and demolition of reinforced concrete structures, namely: manual, mechanical and semi-mechanical method, drilling and blasting method, thermal method. The main advantages and disadvantages of these methods, the possibility and economic feasibility of their use in the interests of the Ministry of Defense of the Russian Federation are also considered. On the basis of the analysis carried out, taking into account the limitations of the use of the methods, a promising electro-hydraulic pulse method for dismantling reinforced concrete structures was proposed and the necessary conditions for its implementation in industrial mastabs in the interests of the Ministry of Defense were indicated.

Keywords: reinforced concrete, reinforced concrete structures, dismantling, demolition, work safety, efficiency, military infrastructure

The results of the development of compositions and technologies for their preparation for use in the structures of marine gravity oil and gas production platforms and underwater oil and gas pipelines are presented. The efficiency of using basalt fiber fibers, plasticizing additive "Sika ViscoCrete 5-800" and soot waste from thermal power plants in the manufacture of fine-grained concrete is proved. As a result of the experiments, the strength characteristics of fiber concrete were determined depending on the amount of superplasticizer and soot waste introduced when using equal-moving mixtures. An increase in the compressive and Flexural strength of samples modified with basalt fiber, superplasticizer and industrial waste is shown, which contributes to an increase in the operational characteristics of oil and gas offshore structures by increasing the parameters of frost resistance and water resistance of structural materials.

Keywords: oil and gas facilities, fiber-reinforced concrete mixture, the superplasticizer basalt fibre, particulate waste strength