scholarly journals Transport systems load-bearing structures state diagnistics and monitoring

2021 ◽  
Vol 7 (4) ◽  
pp. 43-51
Author(s):  
Andrey N. Yashnov ◽  
Lyubov A. Vasilchuk ◽  
Pavel Yu. Kuzmenkov ◽  
Ivan V. Chaplin
Keyword(s):  
Strain State ◽  
Natural Vibration ◽  
Operational Reliability ◽  
Transport Systems ◽  
Vibration Frequencies ◽  
Stress Strain ◽  
Load Bearing ◽  
Stress Strain State ◽  
And Control ◽  
Experimental And Theoretical Studies

Aim: To provide the study and control of the stress-strain state of load-bearing structures during the operation of magnetolevitation transport systems. Methods: Experimental and theoretical studies of dynamic parameters. Results: To assess the stress-strain state of the main load-bearing structures of magnetolevitation transport systems using string superstructure it is proposed to measure the natural vibration frequencies. Conclusion: The organization of diagnostics or monitoring of changes in the natural vibration frequencies of load-bearing structures ensures the operational reliability of load-bearing structures for Maglev.

scholarly journals CONTROL OF ACTIONS OF STEEL TANK IN WORKING

2018 ◽  
Vol 22 (4) ◽  
pp. 66-74 ◽  
Author(s):  
A. A. Vasilkin
Keyword(s):  
Strain State ◽  
Low Cycle Fatigue ◽  
Operating Conditions ◽  
Maximum Effect ◽  
Safe Operation ◽  
Stress Strain ◽  
Load Bearing ◽  
Stress Strain State ◽  
Steel Tank ◽  
Steel Tanks

In steel tanks made by the method of rolling, defects of a geometric shape often occur in the area of the welded welded joint of the wall. Subsequently, in these areas, as a result of low cycle fatigue, an unacceptable defect appears in the form of a crack, which makes it necessary to remove the reservoir from operation and carry out a set of measures for its repair. To determine the terms of safe operation of vertical steel tanks with geometric defects, it is proposed to use the methodology control of the actions of structures of load-bearing structures, one of the directions of which is the regulation of the stress-strain state of steel structures. To implement the possibility of regulating construction, it is necessary to identify such parameters, the change of which will give the maximum effect in achieving the set goals. As the indicated parameters, the design characteristics (material properties, design scheme, geometric characteristics) and factors of external influences (load, operating conditions) can act. To regulate the stress-strain state design of vertical steel tanks, the following regulators are proposed: product loading height, wall deflection arrow and permissible number of tank loading cycles. By numerical calculation of the VAT of the vertical steel tank design with geometric defects, the necessary values and values of the stress state are determined. Further, using known analytical dependencies from the field of fracture mechanics, it is possible to determine the permissible number of loading cycles of the reservoir before the appearance of a crack-like defect. The application of the methodology control of the actions of structures load-bearing structures, by means of a certain change in the established control parameters, allows increasing the number of loading cycles of the reservoir, thereby increasing the period of safe operation of the defective reservoir and thereby increasing the economic efficiency of the tank farm.

scholarly journals Numerical simulation of the stress-strain state of complex-reinforced elements

2019 ◽  
Vol 13 (2) ◽  
pp. 110-115
Author(s):  
Olena Krantovska ◽  
Mykola Petrov ◽  
Liubov Ksonshkevych ◽  
Matija Orešković ◽  
Sergii Synii ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Strain State ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Theoretical Studies ◽  
Stress Strain ◽  
Narrow Strip ◽  
Stress Strain State ◽  
Graphical Environment ◽  
Experimental And Theoretical Studies

The article describes a developed technique of a numerical simulation of the stress-strain state of complex-reinforced elements, which allows you to create models of double-span continuous. The performed experimental and theoretical studies allowed us to carry out the testing of the developed design model and to justify the reliability of the proposed numerical simulation methodology. The results of the experimental studies were compared with those of the theoretical studies. The theoretical calculus algorithm was developed by using the finite element method. Theoretical calculations were performed by using the mathematical-graphical environment software system LIRA-SOFT and the mathematical and computer program MATLAB. On the basis of the experimental research, the iso-fields of displacements and stresses in the materials of an eccentrically compressed beam with a small bend of the slab were constructed, which collapse behind the inclined narrow strip of concrete and displacements and stresses in the materials of the eccentrically stretched beam, which is destroyed due to the yield of the upper mounting armature.

scholarly journals Assessment of the mutual influence of deformation-strength characteristics of the fastening system elements

2019 ◽  
Vol 123 ◽  
pp. 01006 ◽  
Author(s):  
Iryna Kovalevska ◽  
Zenon Pilecki ◽  
Oleksandr Husiev ◽  
Vasyl Snihur
Keyword(s):  
Mine Working ◽  
Strain State ◽  
Mutual Influence ◽  
Strength Characteristics ◽  
Stress Strain ◽  
Load Bearing ◽  
Stress Strain State ◽  
Operation Modes ◽  
Mine Workings ◽  
Rigid Element

The degree of influence has been determined of diversified deformation-strength characteristics of load-bearing elements in the fastening system of the preparatory mine workings, while maintaining them in a laminal massif of soft rocks. The analysis has been performed of multivariate computational experiments of the stress-strain state of the load-bearing elements of the fastening system in the preparatory mine workings from the position of the mutual influence of their deformation-strength characteristics and the support loading as a whole. An analysis is represented of the mutual influence of the operation modes of the mine working support elements between themselves and the fastening system as a whole; it has been studied the stress-strain state of the mine working fastening system with a central hydraulic prop stay, as well as a significant increase in reliability of the support performance has been analysed and determined. The tendency has been substantiated of minimizing the load on the mine working fastening system – increasing the coherence of the diversified operation modes of fastening elements by enhancing preferentially the yielding property of the rigid element. The application has been substantiated of the central yielding prop stays of the strengthening support of a frame in case of intensive rock pressure manifestation in the zone of the stope works active influence.

scholarly journals STUDY OF STRESSED-DEFORMED STATE OF THE POLYGONAL ARCH COVERINGS OF WOOD

World Science ◽  
2019 ◽  
Vol 1 (1(41)) ◽  
pp. 11-14
Author(s):  
O. V. Boіko ◽  
A. O. Boiadzhi ◽  
O. M. Korshak
Keyword(s):  
Strain State ◽  
Stress Strain ◽  
Load Bearing ◽  
Special Steel ◽  
Stress Strain State ◽  
Deformed State

In this work the use of wooden I-beams with OSB wall as the load bearing elements for polygonal arch coverings of buildings of various spans are considered. Special steel connecting pieces can shape the polygonal arch coverings. Calculations of the constructions with a span of 12 and 18 meters and an analysis of their stress-strain state are given.

scholarly journals Modern systems for monitoring the stress-strain state of hazardous power generating facilities

2021 ◽  
Vol 263 ◽  
pp. 02008
Author(s):  
Anatoly Zemlyansky ◽  
Alexander Zhukov ◽  
Daria Bulavina
Keyword(s):  
Residual Stresses ◽  
Construction Industry ◽  
Strain State ◽  
State Level ◽  
Operational Reliability ◽  
Building Structures ◽  
Stress Strain ◽  
Factors Affecting ◽  
Stress Strain State ◽  
Dominant Direction

The paper considers the issue of effectively increasing the level of operational reliability of power generating nuclear and hydraulic facilities. Over the past 20 years, the number of accidents at these facilities has been growing. There are many factors affecting the collapse of structures, but, according to the authors, the lack of a monitoring system capable of fully assessing not only the stress-strain state, but also the so- called “residual” stresses of the material is the dominant direction of research. The same question is raised at the state level, as evidenced by the requirements of the STO, GOST and Federal laws, to which the authors refer below. The legislative prerequisites (requirements) for the creation of an improved system for monitoring critical structures, corresponding to the development trends of the construction industry, as well as the modernization of the existing fund are listed. The drawbacks and advantages of existing monitoring systems (strain gauge, string, fiber-optic sensors and acoustic emission systems) are analyzed in detail, and the general lack of the possibility of measuring, evaluating "residual" stresses in the material of structures is noted. A fundamentally new system for monitoring the stress-strain state of building structures and power equipment is proposed, which is based on the Foerster effect, a comparison is made with the existing systems described above. The main features and capabilities of the method are noted and options for use at highly important facilities are proposed.

scholarly journals Stress-strain state of the building foundations with taking into account the possible water saturation of loess soils

2020 ◽  
pp. 22-31
Author(s):  
Veronika Zhuk ◽  
Oleksandr Piatkov ◽  
Sergiy Tarambula
Keyword(s):  
Strain State ◽  
Water Saturation ◽  
Cost Effective ◽  
Loess Soil ◽  
Soil Base ◽  
Stress Strain ◽  
Engineering Structures ◽  
Load Bearing ◽  
Stress Strain State ◽  
Loess Soils

In Ukraine, the problem of construction on loess soils is relevant due to the widespread use of these soils and their negative property - the ability to give additional deformations of subsidence during water saturation. Flooding of territories by groundwater, emergency leaks from aquifers cause significant problems during the exploitation of buildings and engineering structures on such soils. Computer simulation of the interaction of the building with the soil base allows to investigate the influence of all negative factors on the change of the stress-strain state of both the soil base and the load-bearing structures of the building. The study of the interaction of the building with the foundation was performed using the software package LIRA-CAD. The interaction of the building with the soil base, the soils of which are able to reduce their mechanical properties with increasing humidity and give additional subsidence deformations, was studied. A variant design of the foundations was performed taking into account the occurrence of uneven deformations during subsidence of the loess soil due to its moistening in case of possible emergency losses from aquifers. The change of stress-strain state of the foundations of the building depending on the spatial rigidity of the foundation, the location of the soaking zone within the building spot, the shape and size of the zone of soil moisture is analyzed. It is shown that taking into account the possible water saturation of loess soils when calculating the collaborate of the building with the soil base, allows to obtain stress-strain state of foundations and load-bearing structures of the aboveground part of the building for the most unfavorable conditions that may occur. The search for the optimal variant of the foundation structures of the building, which, while remaining cost-effective, provides reliable operation of the building in conditions of possible occurrence of uneven deformations of subsidence of the soil base during water saturation of the layer of loess soils. According to the research results, a rational variant of the foundation structures has been designed taking into account the possible occurrence of non-uniform deformations.  

scholarly journals Stress-strain state of a combined toroidal baromembrane apparatus

2021 ◽  
Vol 21 (2) ◽  
pp. 123-132
Author(s):  
S. I. Lazarev ◽  
О. V. Lomakina ◽  
V. Е. Bulanov ◽  
I. V. Khorokhorina
Keyword(s):  
Strain State ◽  
Liquid Waste ◽  
The Body ◽  
Transmembrane Pressure ◽  
Toroidal Shell ◽  
Outer Diameter ◽  
Stress Strain ◽  
Load Bearing ◽  
Stress Strain State ◽  
Membrane Apparatus

Introduction. Currently, the purification of wastewater and technological solutions by membrane methods is considered a promising way to neutralize liquid waste. Therefore, the task of developing an engineering method for calculating baromembrane devices is a challenge. Studies on methods involving calculation of design and process variables, membrane equipment design, research of technological features of membrane devices, selection of design schemes, as well as methods of strength and rigidity analysis, are investigated.Materials and Methods. Basic elements of the body of the combined membrane apparatus are considered, a design scheme is proposed, and a method for calculating the strength and rigidity of the main load-bearing element, the cover, is described.  Results. The methods determine the required dimensions of shells and plates for the development of a combined membrane apparatus, and evaluate the strength properties of the devices of this class. The construction elements of the apparatus (primarily, the load-bearing covers) must meet not only the requirements of efficiency and quality of separation and cleaning of solutions, but also the conditions for safe operation. Therefore, the design of the device covers should be based on the optimal design dimensions (thicknesses of round plates, toroidal shells, and support rings). To test the method, the stress-strain state of the membrane apparatus structure was calculated for strength and rigidity. As an example, we consider one cover presented in the form of an open toroidal shell. The evaluation of the application of this technique, taking into account the fact that the shell is mated with a round plate in the inner diameter, and with a ring in the outer diameter, has provided the determination of the required parameters.Discussion and Conclusions. The obtained method of analytical description of the mechanical impact on the elements of the combined apparatus and the example of calculating the toroidal shell and plate, enables to evaluate the stressstrain state of the structure for strength and rigidity. The results of the calculation of covers made of various materials at different pressures are presented. Loading the combined apparatus with transmembrane pressure made it possible to determine the required dimensions of the shells and plates for its design and development. 

Evaluation of strength of carrying metal structures of trailers

2020 ◽  
Vol 2 (100) ◽  
pp. 58-69
Author(s):  
P. Popovych ◽  
L. Poberezhny ◽  
O. Shevchuk ◽  
I. Murovanyi ◽  
T. Dovbush ◽  
...  
Keyword(s):  
External Load ◽  
Strain State ◽  
Deformation Energy ◽  
Strength Analysis ◽  
Preliminary Assessment ◽  
Stress Strain ◽  
Load Bearing ◽  
Metal Structures ◽  
Stress Strain State ◽  
Increased Risk

Purpose: Development of a computational model of stress-strain state bearing elements of trailer frames for preliminary assessment and identification of areas with increased risk of failure. Design/methodology/approach: The object of the study is the processes of loading the load-bearing metal structures of trailers - fertilizer spreaders. The stress-strain state of the spreader bearing system is investigated for the established three typical cases of external load. To refine the values obtained as a result of modelling, they were determined in SOLIDWORKS. Findings: Computational models of load have been compiled by improving the method of minimum potential deformation energy for its effective correct use in analytical studies of a similar type of metal structures. It is proved that for a flat closed frame structure made of thin-walled profiles, loaded with forces perpendicular to the plane of the frame, the levelling of compression and shear energies, as well as axial and transverse forces and bending moments in the horizontal plane does not significantly affect the calculation results. Research limitations/implications: Horizontal components of the shear forces as well as the normal forces and as a consequence the corresponding potential deformation energy are neglected, which has some effect on the accuracy of the calculations. Practical implications: An effective tool for strength analysis with preliminary assessment and diagnostics of load-bearing metal structures based on the constructed calculation models of stress strain state load-bearing frames of typical geometry with an arbitrarily given distribution of external load. Originality/value: A universal algorithm for recording additive functions of bending and torques, as well as the potential deformation energy of welded frames of trailers.

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