Кафедра "Теоретична та будівельна механіка"<br>(з 2022 р увійшла до складу кафедри Технічна механіка ДІІТ) (з 2016 року об’єднано каф. "Теоретична механіка" та каф. "Будівельна механіка")

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http://crust.ust.edu.ua/handle/123456789/9307

ENG: Department "Theoretical and Structural Mechanics" "Theoretical Mechanics" and "Structural Mechanics"

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Analysis of Problem Related to Experimental Data Processing in the Study of the Rolling Stock Influence on the Track
(KTU leidykla „Technologija“, Kaunas, Lithuania, 2022) Bondarenko, Iryna; Keršys, Robertas; Neduzha, Larysa
ENG: In paper discusses the problem of the correctness of the unification of experimental data by axes and points of measurement. The purpose of the study is to analyse experimental data in the study of the influence of the rolling stock on the railway track associated with the change of the nature and ratio of values of forces and stresses when combining data. Experimental data obtained from the study of the influence of Tulpar Talgo on the railway track were considered. The main feature is the construction of a trolley having one wheel instead of two, which makes it possible to show the nature of changes in stresses and forces when grouping data. This made it possible to assess the correctness of the unification in terms of the nature of the force ratio for the passage of rolling stock in the study area.
Analysis of the Dynamics of Freight Cars With Lateral Displacement of the Front Bogie
(Jomard Publishing, Azerbaijan, 2021) Shvets, Angela O.
EN: The importance of traffic safety issues increases with train speed increase. The question of determining the permissible speeds, which is associated with the assessment of the dynamic qualities of the rolling stock is especially important. A quantitative assessment of dynamic indicators can be obtained by the method of mathematical modeling. The article is devoted to the study of the influence of lateral displacement of gondola car bogies on their main dynamic and interaction indicators between rolling stock and rails. Theoretical study is conducted using the model of spatial vibrations of coupling of five cars in the freight train. During the calculations the change in the rotation angle of the central axle of the car body was considered, which leads to the mutual transverse displacement of the bogies. The rear bogie of the freight car is located along the longitudinal track axle, and the front bogie has a transverse displacement corresponding to the rotation angle of the body along the track axle in the range from 0 to 0.01 radians with a plus sign, which increases the striking angle of the front wheel set on the outer rail. As a result of the research, the dependencies of the dynamic indicators of a freight car on the value of the body rotation angle and the movement speed were obtained. Based on the theoretical calculations, the influence of the lateral displacement of the car's running gears on the dynamic qualities of the rolling stock and interaction indicators of the rolling stock with the rail track, taking into account the movement speed along a curvilinear track section with irregularities, is assessed.
Assessment of Locomotive and Multi-unit Fatigue Strength Considering the Results of Certifi cation Tests in Ukraine and EU Countries
(Instytut Kolejnictwa, Warszawa, 2017) Kostrytsya, Sergiy A.
EN: The comparative analysis of methods for assessing the fatigue strength of the rail vehicle used in the Ukraine and the EU is described in this article. As a result of the comparison, the following main diff erences of the indicated methods are distinguished: 1. In Ukraine, fatigue strength assessment is carried out using the fatigue strength factor, which should not exceed the normative value. In the countries of the European Union, the fatigue strength is evaluated according to the permissible stresses, and the permissible stresses are determined using stress strain diagrams. 2. According to the requirements of the Norms in Ukraine for determining the fatigue strength factor, the endurance limits of standard samples in a symmetrical loading cycle are used. Th e stress limit diagrams, which are used in European norms, are constructed for characteristic structural elements taking into account the asymmetry of the stress cycle coeffi cients. Analytic studies and analysis of experimental data carried out by the author have made it possible to develop a number of recommendations aimed at increasing the reliability of the results of estimating the fatigue strength of load-bearing structures of selfpropelled rolling stock and to make proposals for harmonizing the relevant regulatory documents in Ukraine and the EU countries.
The Assessment of Negative Impact of Oil Products on Railroad Track and Rolling Stock Constructions
(Kaunas Univ. of Technology, Lithuania, 2019) Zelenko, Yuliya V.; Lunys, O.; Neduzha, Larysa O.; Steišūnas, S.
EN: Abstract In order to ensure the reliability of metal elements in structures of railway infrastructure, the influence of solutions is investigated that contain oil products on the degree of corrosive changes of steels of grade 3, 5, RSt37-2, 09G2D and grey cast iron 21-40. On the basis of experimental data that were obtained using R-5126 polarization resistance indicator, potentiostat P-5827 mathematical relations of the influence of various fractions of oil products on the rate of metal corrosion are introduced. The obtained data can be used for non-destructive control of basic elements of structures, the choice of effective inhibitors for reducing the corrosive aggressiveness of the environment and the protection of structural elements.
Assessment of the Railway Track Deformability Behaviour as the Parameter of Operational Availability Function
(Printing House “Technologija”, Kaunas, Lithuania, 2021) Bondarenko, Iryna; Keršys, Robertas; Neduzha, Larysa
EN: In paper discusses the problem of the maintenance conditions of the railway track to ensure operational availability in terms of ensuring reliability and maintainability program. The research aims to assess the amount of work spent in railway track deformability under vehicle influence when various railway track stiffness and at different speeds of the vehicle. The research aims to assess the amount of work spent in railway track deformability under vehicle influence when various railway track stiffness and at different speeds of the vehicle. Authors considered the influence of the vehicle speed movement on the vertical dynamic load from vehicle to the rail, the vertical dynamic rail deflection, and vertical dynamic stiffness of the railway track. It allowed estimating the amount of deformability work performed by the rail at vertical load.
Changing the Stress State of the Track Superstructure while Strengthening the Subgrade
(VŠB – Technical University of Ostrava, 2020) Tiutkin, Oleksii L.; Neduzha, Larysa O.; Kalivoda, Jan
ENG: Strengthening the subgrade with the help of various technologies significantly affects the stress state of the track superstructure. The strengthening of the subgrade with piles, leads to an abrupt stiffening of the track superstructure, which is problematic for its normal operation. Two finite element models were created to determine the change in the stress state of the track superstructure when strengthening the subgrade. They fully reflect the geometric, deformation and power characteristics of a real subgrade, which is strengthened by piles. Individual finite elements of the models are provided with the deformation characteristics of the steel rails, reinforced concrete sleepers, soil subgrade, ballast and soil-cement material of piles. The authors carried out the calculation of stress state of the track superstructure for two finite element models. Results are obtained and analyzed to help in choosing the most effective option for strengthening the subgrade.
Coefficient of Stability Against Lift by Longitudinal Forces of Freight Cars in Trains
(IOP Publishing Ltd., 2020) Shvets, Anzhela O.; Shatunov, Oleksandr V.; Dovhaniuk, Stepan S.; Muradian, Leontii A.; Pularyia, Andriy L.; Kalashnik, Vladimir A.
EN: The paper is devoted to a theoretical study of the car movement stability when exposed to longitudinal forces of a quasistatic nature. The authors obtained the expressions for calculating the resistance coefficient of the car lift by the longitudinal compressive force acting on the car as part of a freight train. The influence of some factor’s combination on the longitudinal forces, at which the car movement stability is still maintained, was analyzed using the analytical dependencies to assess the longitudinal loading of cars in trains. The study was carried out by analytical method for assessing the freight car stability when moving at different speeds along curved track sections. The calculations were made in a curve of small radius taking into account the inertia forces from the unbalanced acceleration. In a theoretical study, the influence of quasistatic longitudinal compressive forces depending on changes in speed and force value, as well as the influence of friction in the wheel flange and rail contact and the eccentricity of fastening the automatic coupler shank on the stability were considered. When applying the results obtained, the stability of freight rolling stock can be increased, which in turn will remove some existing restrictions on the permissible speeds and increase the technical speed of train movement. Using the described methodology for determining the lift resistance coefficient will make it possible to justify the cause of derailment, as well as to develop and put into practice technical measures to prevent the lift of carriages, thrusts and shears of the track.
Comparative Analysis of Options for Strengthening the Railway Subgrade with Vertical Elements
(Printing House “Technologija”, Kaunas, Lithuania, 2021) Tiutkin, Oleksii L.; Keršys, Robertas; Neduzha, Larysa
ENG: In paper the task set to investigate and determine the impact of the parameters for strengthening with vertical elements (piles) on the stress and displacement of the track superstructure. The scientific hypothesis is the possibility of selecting such parameters of these elements that minimally affect the stress state of the track superstructure. For this finite-element models of two options for strengthening have been developed. Using a professional complex at different values of deformation characteristics values of displacements and stresses were obtained. The analysis of the stress-strain state for both options reveals that the more effective option of strengthening the subgrade. It has a more positive effect on the deformation state of the subgrade, reduces the vertical displacement of the track superstructure, reduces its stress state, the value of which allows us to testify to the normal operation of the subgrade.
Contemporary Principles for Solving the Problem in Noise Reduction from Railway Rolling Stock
(IOP Publishing, 2020) Zelenko, Yuliia V.; Zelenko, D.; Neduzha, Larysa O.
EN: The statistical and monitoring data confirm the significant impact of the operational mode on the most important noise and vibration parameters, which is relevant for ensuring the efficiency and quality of the operational process with regard to ergonomic and environmental requirements. The article analyzes the acoustic parameters of rolling stock of the railway, emphasizes the peculiarities of noise emission from various elements of rolling stock and a track. Existing approaches towards solving the problem in the organization of railway noise control are outlined. On the basis of existing modern methods for measurement and analysis of acoustic parameters, the authors propose conceptual approaches toward monitoring the acoustic parameters, predicting noise characteristics and constructing the noise maps of railways. The algorithm of the developed acoustic model for the operational monitoring of noise load and the possibility to compile a case of noise maps for Ukrzaliznytsia is presented. The proposed algorithm allows at given basic design parameters and speed of rolling stock, known sound-absorbing and dissipative characteristics of all elements to carry out a rational selection of noise-protective measures in accordance with the sanitary noise regulations for a specific receptive facility.
Correlations Between Transportation and the Covid-19 Pandemic
(AIP Conference Proceedings, 2022) Barberi, Salvatore; Arena, Fabio; Termine, Francesco; Canale, Antonino; Olayode, Isaac Oyeyemi; Neduzha, Larysa; Zuccalà, Yuri
ENG: COVID pandemic has abruptly changed people habits and lifestyles worldwide, including the usage and perception towards all the different transportation systems; to this date (mid-2021), the pandemic has been going on for over a year now, and there is still no certainty about when it will end. A drastic decline in the number of commercial flights both national and international has happened, as a consequence of the lockdown policies adopted by the various countries around the globe in order to prevent the infection from spreading around, and with variable trends depending on the period and the reciprocal agreements between the various states. Land-side public transportation too has witnessed a backlash mainly due to similar policies or even not leaving home during lockdowns, often working remotely from home, and switching from public transportation to driving, walking or cycling if necessary. COVID-19 and transport are linked by a two-way relationship: if it is true that COVID-19 impacts on transport systems, it is also true that transport systems, in turn, have a very important role in the spread of the pandemic. Swabs first and vaccines recently, are raising new hopes about the pandemic ending soon. The consequences of COVID-19 will in any case be significant, and will revolutionize the way of conceiving transport, meaning new challenges for scientific research.
Determination of the Issue Concerning the lift Resistance Factor of lightweight Car
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2015) Shvets, Anzhela O.; Zheleznov, Konstantine I.; Аkulov, Artem S.; Zabolotnyi, Oleksandr M.; Chabaniuk, Evhen V.
EN: Purpose. The analytical study of the connection between the longitudinal force, acting on the light-weight car, lateral and vertical forces of interaction in the contact zone «wheel – rail» with the lift resistance factor value is to provide a simple relationships between them. Methodology. Research was conducted by the method of mathematical modeling of loading the freight car when driving at different speeds on straight and curved sections of a track. Findings. Even in the absence of «lift» accordingly the classical train stability theory, as the hinge-rod system, the presence of the longitudinal compressive forces may become a factor provoking cars derailment. The main reason of wheel climbing on rails is the combination of processes of dynamic interaction between the hunting vehicle and the track with simultaneous action of longitudinal compressive forces, and not the destabilization of train as a hingedrod system. To assess the impact of the longitudinal forces value on the lift resistance factor there are presented the calculation results for the empty gondola car motion, model No. 12-532, on 250 m radius curve with 150 mm rise and cross starting of car underframe relating to the track axis in 50 mm guiding section. The calculations were made in such a curve excluding the inertial forces from outstanding acceleration and taking into account the unbalanced acceleration with the permissible speed of 65 km/h. Originality. This study provides the technique of determining the lift resistance factor by longitudinal forces, which is somewhat different from the standard one, as well as evaluates impact of rolling stock speed on this factor. Practical value. The authors clarify the current method of determining the lift resistance factor by longitudinal forces and assess the impact of rolling stock speed on the value of this factor. From these studies one can conclude that because of cars hunting their lift is possible even when the train as hinge-rod system does not lose stability. The developed proposals allow reducing the number of car derailment by taking into account important parameters and characteristics during the process of calculation and design that increase their stability in the rail track especially in case of increased speed of freight trains.
Determination of Up-To-Date Directions of Development of Domestic System of Testing and Certification of Railways Rolling Stock
("Ukrmetallurginform" STA", Ltd, Dnipro, 2016) Fomin, Oleksij V.; Murashova, Nataliia H.; Shvets, Angela A.
EN: In the paper, researches results of development of system of tests devoted to up-to-date directions determination and certification of rolling stock and its components are provided. Necessity of synchronization of diagrams and domestic standards of test and certification activities in the field of rolling stock with European legislation is proved. Results and features of the experience analysis of appropriate types of activity of the European countries advanced enterprises are provided.
Determining the Causes of Rolling Stock Derailment From the Track Using Modern Research Methods
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Kuzyshyn, Andriy; Batig, Andriy V.; Sobolevska, Julia H.; Kostritsa, Sergei A.; Ursulyak, Lyudmila V.; Dovhaniuk, Stepan S.
EN: Abstract. The analysis of cases of rolling stock derailment from the track at PJSC «Ukrzaliznytsia» over the past 5 years has been carried out and their main types are given. It is noted that the rapid development and improvement of computer technology allows the use of computer and mathematical modelling in the study of cases of rolling stock derailment from the rail track, which makes it possible to take into account a combination of factors that have the main influence on the behavior of rolling stock when moving along the track. It has been established that the first step is the construction of a mathematical model of an object using a selected type of mathematical description: algebraic, differential, integral equations, discrete mathematics, set theory, and others. And the second step is the choice of a method for solving these models. The simulation methods are given, which, depending on the programming style, are divided into: procedural-oriented, object-oriented, logical-oriented, rule-oriented, and oriented to constraints. An objectoriented programming of a freight car has been developed, which will make it possible to evaluate its main dynamic indicators, in particular, indicators of stability from derailment. This in turn will facilitate the establishment of the main causes of rolling stock derailment from the rail track.
Dynamic Indicators Influencing Design Solution for Modernization of the Freight Rolling Stock
(University of Belgrade, Faculty of Mechanical Engineering, 2021) Shvets, Anzhela O.
EN: Rolling stock directly affects the economic indices of the transport industry and the national economy as a whole, leading to the need to improve control and quantify of the rolling stock dynamic load in order to maintain safe and reliable rail connections. In the process of rolling stock designing and operating, a quantitative assessment of dynamic loads is an urgent scientific and technical problem. The article presents an analysis of theoretical studies of the rolling stock dynamic characteristics on the example of open wagons, flat wagons and hopper wagons. The loading modes influence on the dynamic loading of the wagon has been studied with the aim of solving the problem of predicting the dynamics of rolling stock and indicators of its interaction with the track. The results of theoretical studies are presented taking into account the motion speed along the curved track of short and medium radius.
Dynamic Interaction of a Freight Car Body and a Three-Piece Bogie During Axle Load Increase
(Taylor & Francis, England, 2021) Shvets, Angela O.
UKR: The article presents the results of theoretical studies of interaction process of a freight car body with a three-piece bogie, which are aimed at solving the relevant problem of increasing the permissible speeds at railways with 1520 mm track gauge under conditions of linear load increase on the wheel set axle. The purpose of the research was to propose such an approach to the study of interaction processes between rolling stock and track, taking into account the interaction model of neighbouring carriages in trains, which will allow more correctly take into account the dynamics of rolling stock and increase traffic safety. The oscillation frequencies of the body, bogie and wheel set are analysed in order to establish a possible resonance phenomenon. The article examines the longitudinal and transverse forces of pseudo-sliding (creeping) arising between the climbing wheel of the front bogie and the rails. The conducted studies can contribute to the replacement of 18-100 bogies with modernised three-piece bogies while maintaining the main most metal-consuming elements of the 18-100 model implementing some modernisation units. The results obtained will make it possible to revise the permissible vehicle speeds with an increased axle load.
Dynamic Sustainable Processes Simulation to Study Transport Object Efficiency
(MDPI, Basel, Switzerland, 2022) Bondarenko, Iryna; Severino, Alessandro; Olayode, Isaac Oyeyemi; Campisi, Tiziana; Neduzha, Larysa
ENG: The development of reliability theory has led to the setting of tasks requiring consideration of the efficiency and functional safety of technical objects of transport over the life cycle. The paper demonstrates the possibility of using the universal laws of elastic wave theory to describe natural phenomena occurring in complex dynamic systems, on the examples of solving issues arising in the interaction of rolling stock and the railway track. The accounting of the time component and the ability of elastic waves to propagate energy in time and space allowed considering any interaction process as a chain of processes, incidence-reflection-refraction of force impulses of interaction. Understanding the physics of dynamic processes that occur in objects while performing their intended functions allows developers to improve objects in such a way as to minimize their life cycle cost and maximize their ability to perform their intended functions under different operating conditions. In addition, it allows the expansion of existing methods and approaches to diagnostics of dynamic transport systems. All this is a base for making it possible to develop an innovative and effective tool for engineers and scientists to assess the impact of technosphere transport objects on human habitats.
Dynamic Track Irregularities Modeling when Studying Rolling Stock Dynamics
(Kaunas Univ. of Technology, Lithuania, 2019) Bondarenko, Iryna O.; Lunys, O.; Neduzha, Larysa O.; Keršys, Robertas
ENG: Abstract The main purpose of this work is to study the process of transferring forces in the interaction of the rolling stock and the railway track in time. It was considered the wheel set movement on a straight track section without taking into account the rolling stock movements in the horizontal plane caused by the wheel conicity. And it was obtained the dynamic track irregularities depending on the rolling stock speed in the cross section of the railway track when a single force passes over it. Using the wave properties during the force propagation in the trackform elements is allowed to determine the time response of the elements to the force action. First, it allowed to take into account the influence of the state of the trackform elements on the work of the trackform itself and to obtain dynamic track irregularities that take into account both the length inhomogeneity and the depth anisotropy of the trackform. Secondly, it allowed to determine the change in strain in the trackform elements in time.
Effect of the State of Car Running Gears and Railway Track on Wheel and Rail Wear
(Technical University of Budapest, Budapest, 1998) Blokhin, Evgen P.; Pshinko, Oleksandr M.; Danovich, Viktor D.; Korotenko, Mykhaylo L.
EN: This paper presents the results of theoretical research and real condition experiments which were conducted with the purpose of determining the influence of the open goods wagon running gear characteristic parameter deviations from their nominal values on the wheel and rail wear. The experimental results has confirmed the reliability of conclusions made on the basis of modelling.
Effective Jet-Grouting Application for Improving the State of Deformation of Landmarks
(MDPI, 2022) Severino, Alessandro; Wahrhaftig, Alexandre de Macêdo; Tiutkin, Oleksii L.; Gubashova, Valentyna; Neduzha, Larysa
ENG: The problem of improving the state of deformation of landmarks is an important aspect when performing civil services, because they have a historical interest and bring symbolisms which relate to an event of particular interest for the community. The engineering–geological surveys, technical evaluation and operational suitability of landmarks of national significance are performed to improve the state of deformation. The conducted analytical assessment of landslide hazard slope stability in the RocScience Slide computational complex shows that in the presence of landslide prevention works, and the stability coefficient is increased by a factor of 1.21–1.37. The regularities of deformation and strength parameters of the soil–cement obtained during the jet-grouting application indicated an increase in strength gain of amplifier elements by an average of 1.6–4.0 times. This proves the effectiveness of the jet-grouting application for improving the state of deformation of landmarks of national significance.
Enhancement of Operational Reliability of Elements in the Diesel Engine Cooling System of Locomotives
(Kaunas Univ. of Technology, Lithuania, 2020) Zelenko, Yuliia V.; Keršys, A.; Neduzha, Larysa O.
EN: Operating experience of diesel locomotives on railways shows that the use of insufficiently purified water results in the destruction of water cooling systems. This problem is especially acute for areas with increased hardness and mineralization of natural waters. The impact of the water demineralization degree on the corrosion rate of elements in diesel engine cooling systems of locomotives has been researched. The dependence of the corrosion rate for various metals on the degree and depth of desalination and the cooling liquid temperature is proved. Recommendations on optimizing the technology of cation treatment for cooling liquids ensuring the efficiency and durability in the operation of diesel engines of locomotives were developed.

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