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Analysis of Feasibility for Implementing European Standard Railway Tracks in Ukraine
(Kaunas University of Technology, Kaunas, Lithuania, 2023) Kurhan, Mykola; Kurhan, Dmytro; Hmelevska, Nelya
ENG: The contemporary challenge at hand pertains to the development of theoretical, methodological frameworks, and practical guidelines for establishing railway mainlines in Ukraine aligned with European standards. The objective of this research involves scrutinizing diverse scenarios and, based on this analysis, evaluating the prospects of constructing European standard railway tracks within Ukraine. The introduction of a 1435 mm gauge railway network on a new route within Ukraine necessitates substantial investments in transport infrastructure construction and procurement of rolling stock. An unbiased assessment and definitive determination of prospective directions demand an examination of key criteria characterizing rail-oriented agglomeration tendencies and the volume of transit transportation for both passengers and freight. Additionally, the analysis takes into account the techno-economic potential of these directions.
Analysis of Stress-Strain State Changes in Railway Tracks During Transition to European Gauge
(IOP Publishing, 2024) Fischer, Szabolcs; Kurhan, Dmytro; Kurhan, Mykola; Hmelevska, Nelya
ENG: The geographical location of Ukraine facilitates its integration into the transportation network connecting European countries. Various options exist for transitioning from the gauge of 1 520 mm to the European standard gauge of 1 435 mm. This paper aims to analyze the changes in the stress-strain state of railway track elements during the reconstruction of existing sections from the 1 520 mm gauge to the 1 435 mm European gauge or to a dual gauge of 1 435/1 520 mm. To perform these calculations, a spatial model of dynamic deformations in the railway track is employed, based on the principles of elasticity theory. The results of the analysis indicate that the post-reconstruction railway track elements do not exceed permissible stress levels. However, the implementation of a combined railway track complicates the stress state of the ballast layer, leading to asymmetric stresses along the length of the sleepers, which vary depending on the track on which trains operate. There will also be a redistribution of stresses acting on the ground structure, which remains in place after years of operation. The research results identify changes in the stress-strain state of the railway track and can be used to justify measures for the appropriate reinforcement of the ballast layer and the ground structure. Keywords: railway track, stress-strain state, ground structure, European standard gauge, reinforcement of the ballast layer.
An Analytical Method for Determining the Stress–Strain State of a Subgrade with Combined Reinforcement
(MDPI, Basel, Switzerland, 2024) Alkhdour, Ahmad M.; Tiutkin, Oleksii L.; Fischer, Szabolcs; Kurhan, Dmytro
ENG: This article presents the fundamentals of an analytical method for determining the stress–strain state of a railway subgrade reinforced with geosynthetic material. The reinforcement described is a combined system where the geosynthetic material forms an open shell containing a layer of compacted crushed stone. The overall stress–strain state is proposed to be viewed as a superposition of two states of the subgrade. The stresses and displacements in the first state refer to the unreinforced subgrade (matrix), while the stress–strain state of the reinforcement element is determined using analytical constructs from composite theory. The dependencies of the overall stress–strain state are applied in a numerical analysis, which confirms the positive effect of reduced subgrade deformations. A small-scale experimental model further validates the accuracy of the analytical approach.
Application of Prefabricated Retaining Walls with Increased Shear Resistance to Ensure Tailings Dam Stability
(IOP Publishing Ltd, 2024) Timchenko, R. O.; Krishko, D. A.; Kozariz, V. Ya.; Nastich, O. B.; Tiutkin, Oleksii L.
ENG: Tailings ponds and sludge storage facilities do not currently meet modern standards that regulate the requirements for operational safety, reliability, stability and durability. The research considers new constructive solutions for retaining walls with increased shear resistance due to passive soil resistance. Schemes and designs of tailings dams are analyzed. A comparative analysis is carried out using recommended methods to determine the safety factor for the design slip curves. The regularities of the influence of multilayer nonlinearly deformed backfill and external loads are established and new principles for determining the horizontal pressure on the retaining wall are formulated. The development of new design solutions for retaining walls and calculation methods for determining the lateral pressure of multilayer backfill is an urgent scientific task. Consideration of the influence of a multilayer nonlinearly deformed massif under external loading allows formulating new principles for determining the horizontal pressure on the retaining wall.
The Centrifugal Modeling of Reinforcement on Approaches to Railway Bridges
(Óbuda University, Budapest, Hungary, 2022) Alkhdour, Ahmad M.; Tiutkin, Oleksii L.; Marochka, Vitalii V.; Boboshko, Stepan H.
ENG: The purpose of the research is to test models of sections with transient stiffness on approaches to railway bridges in the laboratory. The feasibility of the proposed methods of reinforcing the transient stiffness areas to ensure normal operation and avoid the formation of significant deformations had been tested. Centrifugal simulation of three types of reinforcement of transition section had been performed. The deformations of the models of the section with transient stiffness on approach to the railway bridge had been obtained. A comparative analysis of the results of centrifugal experiments had been performed. The effectiveness of each of the reinforcement options had been determined and the most rational method of reinforcement had been concluded.
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.
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.
Comparative Analysis of the Results of Calculating the Stability of a Reinforced Subgrade with Geosynthetic Materials
(Kaunas University of Technology, 2021) Andrieiev, Volodymyr S.; Tiutkin, Oleksii L.; Hubar, Oleksіy V.; Markul, Ruslan V.
ENG: Тhе article presents the results of studies of the stress-strain state of the reinforced and unreinforced railway subgrade. Тhis study compares changes in the distribution of stresses and displacements in а railway subgrade. Comparisons of stresses and displacements made it ossible to obtain: - comparative analysis of the work of the main site of the subgrade under increased load with reinforcement and without reinforcement; - comparative assessment ofthe efficiency ofthe reinforced subgrade at increased load; - isolines and isofields of displacements and stresses in the body ofthe embankment at an increased load.
The Comparative Analysis of the Stress-Strain State of the Support of the Escalator Tunnel Constructed in Weak Soils by the NATM
(IOP Publishing Ltd, 2022) Radkevych, Anatolii V.; Tiutkin, Oleksii L.; Kuprii, Volodymyr; Bielikova, Sofiia
ENG: The construction of underground objects of the subway is always associated with building of structures connecting the surface. For subways, such structures are escalator tunnels. During the construction of the Dnipro Metro, these underground structures are built using a new technology that forms a multilayered support. This technology is the New Austrian tunneling method. A special feature of its application under the conditions of the Dnipro city is the existence of weak rocks in the upper part of the escalator tunnel. To ensure their stability, various special operational techniques are used that impact the rock massif. The basic techniques include artificial freezing, which was the dominant strengthening technology, and chemical strengthening (cementation), which is more consistent with the New Austrian tunneling method. To elucidate the effectiveness of the two strengthening techniques, a finiteelement model of the Dnipro Metro escalator tunnel has been built. The numerical calculation of two variants for the strengthening of weak soils yielded results for a comparative analysis of the stress-strain state. The result of the comparative analysis is the conclusion of greater cementation efficiency when strengthening weak soils of the massif in which the escalator tunnel is constructed using New Austrian tunneling method.
A Comprehensive Procedure for Estimating the Stressedstrained State of a Reinforced Concrete Bridge Under the Action of Variable Environmental Temperatures
(РС ТЕСHNOLOGY СЕNTЕR, Kharkiv, Ukraine, 2021) Kovalchuk, Vitalii V.; Onyshchenko, Artur; Fedorenko, Olexander; Habrel, Mykola; Parneta, Bogdan Z.; Voznyak, Oleh M.; Markul, Ruslan V.; Parneta, Mariana; Rybak, Roman
ENG: This paper reports the full-scale experimental measurements of temperature distribution over the surfaces of bridges’ steel-concrete beams under the influence of positive and negative ambient temperatures. It has been established that the temperature is distributed unevenly along the vertical direction of a bridge’s steel-concrete beam. It was found that the metal beam accepted higher temperature values. The maximum registered temperature difference between a metal beam and a reinforced concrete slab at positive ambient temperatures was +9.0 °C, and the minimum temperature difference was −2.1 °C. The mathematical models for calculating a temperature field and a thermally strained state of bridges’ steel-concrete beams under the influence of variable climatic temperature changes in the environment have been improved, taking into consideration the uneven temperature distribution across a bridge’s reinforced concrete beam. The possibility has been established to consider a one-dimensional problem or to apply the three-dimensional estimated problem schemes as the estimation schemes for determining the thermoelastic state of reinforced concrete bridges. The temperature field and the stressed state of bridges’ reinforced concrete beams were determined. It was found that the maximum stresses arise at the place where a metal beam meets a reinforced concrete slab. These stresses amount to 73.4 MPa at positive ambient temperatures, and 69.3 MPa at negative ambient temperatures. The amount of stresses is up to 35 % of the permissible stress values. The overall stressed-strained state of a bridge’s reinforced concrete beams should be assessed at the joint action of temperature-in- duced climatic influences and loads from moving vehicles.
Controlling the Dynamic Characteristics of Steel Bunker Containers for Bulk Materials
(IOP Conference Series: Earth and Environmental Science, 2024) Bannikov, Dmytro O.; Tiutkin, Oleksii L.; Hezentsvei, Yukhym; Muntian, Antonina O.
ENG: The article presents the main results of research devoted to the definition and analysis of the dynamic characteristics of steel small-sized bunker containers for storing bulk materials. All studies were carried out using the finite element method with the use computer complex SCAD. The object of research was a bunker of a bypass track for feeding bulk materials with a total volume of up to 70 m3. The study analysed the natural partial frequency spectrum and the partial oscillation modes of individual load-bearing elements of the bunker. Based on the results of the data analysis, a rather high quantitative density of the natural frequency spectrum was determined. At the same time, its lower limit is about 25-30 Hz for an empty bunker capacity and decreases to 3-5 Hz when the bunker is fully loaded, which is dangerous from the point of view of the possibility of resonance phenomena. In order to qualitatively and quantitatively control the dynamic characteristics, it was proposed to change the steel strength of the structure, which made it possible to change the natural frequencies by about 15% for every 100 MPa change in steel strength for the bunker containers of the considered type.
Determination of the Type and the Length for the Transition Curves on the Directions of High-Speed Train Operation
(Széchenyi István University, Győr, Hungary, 2022) Kurhan, Mykola ; Kurhan, Dmytro ; Husak, Marina ; Hmelevska, Nelya
ENG: In many countries around the world, a cubic parabola is used as transition curves in a simplified form. Today, the properties of many mathematical curves are well studied, which can be used as transition curves. The object of research is the process of restructuring transition curves when organizing high-speed trains operation. The use of modern means of mathematical modelling allows to add a number of dynamic characteristics for evaluation parameters of motion in the curved sections of the tracks. Thus, with an increase in speed for transition curves, both the values of unbalanced acceleration and its change in time, and also the velocity attenuation of oscillations of rolling stock when moving from a transition curve to a circular curve or to a direct section. On the basis of the conducted research, it has been found that when increasing the speed of the vehicle movement in the range from 120 to 200 km/h, the length of the stabilization section increases at the output of the curvature by an average of 20 m for every 40 km/h. The analysis showed that with correctly set parameters of transition curves, which correspond to the maximum speed of movement and radius of a circular curve, the strength and reliability of the bearing elements in the structure of the permanent way and the travel comfort are fully ensured.
Determining Features of the Deformed State of Reinforced Concrete Beams of Road Bridges When Strengthening the Span Structures
(РС Тесhnology Сеntеr, Kharkiv, Ukraine, 2022) Kliuchnyk, Serhii; Spivak, D.; Goryushkin, I.
ENG: The technology of repairing reinforced concrete bridges typically involves closing traffic on one half of the structure and performing work on it when it is possible to move vehicles on the second part of this structure. The main process of interest to practitioners in terms of hardening concrete, which occurs in the beams of a span structure during the passage of a temporary moving load, is deformation. By the time the cement of freshly laid concrete of the overhead reinforcement slab is hardened, it is necessary to create the necessary conditions for this (temperature, humidity, immobility over time, etc.). Before concrete acquires strength, movements arising in the span structure cause the destruction of cement stone at the formation stage. It is necessary to investigate the presence of deformations, as well as their impact on the impossibility of forming a homogeneous structure of concrete and its adhesion to reinforcing elements that combine the existing slab with the new one. This study has established deformations induced by a temporary load from 1.61 to 5.83 mm, which have a negative impact on the process of solidification of concrete in the reinforcement slab for a span structure during the repair of a motorway bridge. The three-dimensional models were calculated by simulating a bridge of the M-04 highway. The results underlie the conclusions that the technology of repair work does not take into consideration the required conditions for high-quality concrete strength acquisition in an additional slab. The study results established that operations on concreting an additional overhead reinforcement slab in the presence of vibrational effects exerted by the temporary load on the span structure cannot be performed because of the destruction of concrete at the hardening stage. Given the above issue, several ways to address it have been devised and analyzed; the best of them is recommended.
Determining the Deformation Characteristics of Railway Ballast by Mathematical Modeling of Elastic Wave Propagation
(MDPI, 2023) Kurhan, Dmytro ; Kurhan, Mykola ; Horváth, Balázs; Fischer, Szabolcs
ENG: The article solves the problem of theoretically determining the deformable characteristics of railway ballast, considering its condition through mathematical modeling. Different tasks require mathematical models with different levels of detail of certain elements. After a certain limit, excessive detailing only worsens the quality of the model. Therefore, for many problems of the interaction between the track and the rolling stock, it is sufficient to describe the ballast as a homogeneous isotropic layer with a vertical elastic deformation. The elastic deformation of the ballast is formed by the deviation of individual elements; the ballast may have pollutants, the ballast may have places with different levels of compaction, etc. To be able to determine the general characteristics of the layer, a dynamic model of the stress–strain state of the system based on the dynamic problem of the theory of elasticity is applied. The reaction of the ballast to the dynamic load is modeled through the passage of elastic deformation waves. The given results can be applied in the models of the railway track in the other direction as initial data regarding the ballast layer.
Determining the Strained State of Prefabricated Metal Corrugated Structures of a Tunnel Overpass Exposed to the Dynamic Loading from Railroad Rolling Stock
(РС Тесhnology Сеntеr, Kharkiv, Ukraine, 2022) Kovalchuk, Vitalii V.; Koval, Maksym; Onyshchenko, Artur; Kravets, Ivan B.; Bal, Olena M.; Markul, Ruslan V.; Vikhot, S.; Petrenko, Oleksiy V.; Rybak, Roman; Milyanych, Andriy R.
ENG: This paper reports the analysis of prospects for the use of prefabricated metal corrugated structures in the body of the embankment of a railroad track in the form of a tunnel overpass in order to pass road vehicles and railroad rolling stock. A technique of inertial dynamic tests of the deformed state of a tunnel overpass from prefabricated metal corrugated structures during the passage of railroad rolling stock is given, by measuring accelerations at the top and on the sides of overpass structures. An algorithm is proposed for processing the acceleration signal for assessing the strained state of metal corrugated structures of a tunnel overpass under the action of dynamic load from railroad transport. Experimental dynamic measurements of accelerations arising at the top and on the sides of a tunnel overpass during the passage of passenger and freight railroad rolling stock were carried out. The maximum value of accelerations arising at the top of a tunnel overpass during the passage of a freight train was 7.99 m/s2, and when passing a passenger train – 6.21 m/s2; the maximum accelerations that occur on the sides were 2.63 m/s2 and 1.77 m/s2. It is established that the maximum deformations of metal corrugated structures of the top of a tunnel overpass, when passing freight and passenger trains are, respectively, 1.63 mm and 1.11 mm. The maximum strains of metal corrugated structures on the sides of an overpass are 1.07 mm and 0.48 mm. The value of relative deformations in the vertical and horizontal dimensions of the structures of a tunnel overpass under the action of dynamic loads from the railroad rolling stock has been found. The relative vertical strains of an overpass amounted to 0.020 %; horizontal – 0.012 %. The practical significance of this work is that with the help of the devised procedure for measuring accelerations, it is possible to assess the strained state of metal corrugated structures under the influence of dynamic loads from the railroad rolling stock.
Development of Devices for Long-Term Railway Track Condition Monitoring: Review of Sensor Varieties
(Óbuda University. Budapest, Hungary, 2025) Kurhan, Dmytro; Kovalchuk, Vitalii V.; Markul, Ruslan V.; Kovalskyi, Denis
ENG: There are numerous methods for monitoring the condition of railway tracks. In most cases, either the geometry of the railway track or its interaction parameters with moving trains are checked. This work is a component of a project aimed at developing a methodology for installing sensors (sensor networks) for continuous (long-term) monitoring of railway track condition. Therefore, its main objective is to analyse and discuss interim results regarding the feasibility of applying various types of sensors installed on railway track elements. The authors considered three options for sensor application for the overall assessment of railway track condition: measuring stresses in rails with strain gauges, measuring accelerations of rail and sleeper vibrations with accelerometers, and measuring the speed of wave propagation in ballast. Each method has its own advantages and disadvantages. Considering the analysis conducted, each method, both independently and in combination with others, can be applicable for building systems for long-term monitoring of railway track condition. Such systems can be useful, both for solving practical track maintenance tasks during operation and for scientific research.
Development of High-Speed Railway Network in Europe: A Case Study of Ukraine
(Budapest University of Technology and Economics, Budapest, Hungary, 2024) Kurhan, Mykola; Fischer, Szabolcs; Tiutkin, Oleksii L.; Kurhan, Dmytro; Hmelevska, Nelya
ENG: The current task today is the development of theoretical and methodological approaches, as well as practical recommendations for determining the technical feasibility of creating high-speed railway (HSR) lines in the European context. The development of railways in individual countries, followed by the creation of a pan-European high-speed railway network, has raised questions about the compatibility of the technical systems of individual national HSRs. This paper addresses these issues using the example of Ukraine. The research is based on an analysis of scientific developments related to the design of HSR lines and the synthesis of European experience in identifying priority route directions in Ukraine. For comparing various scenarios for the development of railway connections, the authors have developed a forecasting and efficiency assessment model based on the Net Present Value (NPV) indicator. It has been demonstrated that considering the population attracted to HSR and the volume of transit passenger transportation alone is insufficient to achieve the normative investment payback. This situation can only be rectified by implementing mixed traffic involving high-speed passenger trains and accelerated freight trains. However, mixed traffic of passenger and freight trains on high-speed rail lines may face numerous issues and constraints that require careful planning and coordination.
Development of Methods to Increase the Efficiency of Railway Maintenance
(ScientificRoute OÜ publisher, Tallinn, Estonia, 2022) Patlasov, Oleksandr M.; Fedorenko, Yelyzaveta; Shulha, Denys
ENG:Object of research: technology of track maintenance optimization. Solved problem: In the development of decisions to optimize the decision-making system in the content of the upper structure of the track used methods of control theory, systems analysis, methodology of optimal control. Main scientific results: An analysis of the degrees of research on improving the efficiency of the technical management of railways showed that there was no systematic approach and that existing developments in the organization, in particular the relative optimization, Separate track repair standards or take into account parameter models, process requirements and conditions. Area of practical use of research results: industrial enterprises, railway stations. Providing the stable support of the railway, sustainable and rhythmic operation of railway traffic is ensured. About 7.3 thousand km are exploited in the ferrous metallurgy of Ukraine. More than 70 % of routes are up to 500 km long and belong to a large company. Consequently, an important task is to maintain the technical state of railways at the production demands level. Innovative technological product: combined transportations that can interact with similar networks of foreign countries. Scope of application of innovative technological product: formation and effective functioning of railway-transport complex, improvement of tariff policy, substantiation of perspective parameters of transportation process and its technical means, creation of advanced technologies, choice of rational structure of transport network, formation of transport corridors, development of fundamentally new management systems.
Development of the High-Speed Running of Trains in Ukraine for Integration with the International Railway Network
(Óbuda University, Budapest, Hungary, 2022) Kurhan, Dmytro ; Kurhan, Mykola ; Hmelevska, Nelya
ENG: Most European countries successfully solve the problem of national passenger transportation due to a significant increase in speed. Such measures are carried out both on existing railways through their modernization, and on specially built lines. Mass passenger transportation along the HSN has confirmed their extremely high reliability, safety, economic efficiency, ecological cleanness, and attractiveness for passengers. The creation of international networks based on the potentials of individual countries leads to the need for establishing the following operational and technical parameters of domestic high-speed railway lines, which would have operational compatibility with the Trans-European HSN. The interconnection between the volume of passenger traffic with the specified factors allows to predict promising passenger flow and evaluate the effectiveness in the organization of high-speed running in a particular direction. The economic integration of countries in the European Union allows increasing passenger flows on international travel. This circumstance leads to the problem solution in connecting national high-speed highways into a single European network.
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.

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