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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.
The Analytic Hierarchy Process as a Cognitive Tool for Evaluating Switch Components
(CogSust Nonprofit Ltd., Budapest, Hungary, 2025) Kurhan, Mykola; Kurhan, Dmytro; Baidak, Serhii; Khmelevskyi, Vladyslav
ENG: The purpose of this study is to improve the approach to the comprehensive evaluation of switch elements by applying the Analytic Hierarchy Process (AHP). This method makes it possible to determine their priority according to safety and efficiency criteria, as well as to justify optimal strategies for modernization and reconstruction under conditions of increasing train speeds. The scientific approach involves the use of AHP with consideration of the specific operational features of switches on high-speed railways. In particular, the study accounts for higher safety and speed requirements, decreasing maintenance costs, and the reduced service life of structural components. A hierarchy of criteria was developed, along with pairwise comparisons, the calculation of weighting coefficients, and an integrated assessment of alternatives. The application of AHP enabled the determination of the priority of each switch type based on the criteria of traffic safety, speed, operational costs, and service life. According to the analysis, the priorities of the main switch elements were established as follows: frog – 0.395; closure curve – 0.234; switch blade – 0.190; switch curve – 0.181. These results confirm that the frog is the most critical element in terms of its overall impact on safety, speed, and maintenance costs, which is primarily due to its structural complexity and high wear rate (especially under dynamic loads). The findings provide a basis for informed decision-making regarding the prioritization of repair or replacement of individual structural elements, considering the operating conditions of high-speed lines.
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.
Assessing the Feasibility of Electric Road Transport in Europe Using the Integral Emissions Index
(The Silesian University of Technology, Katowice, Poland, 2025) Bosyi, Dmytro O.; Zemskyi, Denys R.; Biltsan, Kostiantyn M.; Borycheva, Svitlana V.
ENG: This article reviews the development of electric road transport and assesses its feasibility in European countries based on an analysis of CO₂ emissions using an integral index. Electric road transport is evolving in three main directions: battery-powered vehicles, hydrogen fuel cell vehicles, and road electrification. Battery electric vehicles are widely used, but their future may be constrained by issues related to cost, charging infrastructure, and raw material availability. Hydrogen-powered vehicles offer fast refueling but require substantial investments and strict safety standards. Road electrification includes both contact and wireless energy transfer systems. Contact-based systems, in particular, provide high power and low energy losses, making them optimal for vehicles with significant energy demands. The environmental efficiency of electric vehicles largely depends on the electricity source. Countries with a high share of renewable energy, such as Norway and France, demonstrate greater environmental efficiency in electric vehicle adoption. Special attention should be given to road electrification, which reduces the duration of battery-powered autonomous driving and allows for smaller battery sizes, thereby extending their lifespan. This approach not only increases battery longevity but also has a positive environmental impact by reducing emissions associated with battery production and disposal.
Assessment of Combined High-Speed Passenger and Freight Train Movement to Mitigate Environmental Impact
(IOP Publishing Ltd, 2025) Kurhan, Mykola; Fischer, Szabolcs; Kurhan, Dmytro; Hmelevska, Nelya
ENG: The purpose of the study is to investigate the primary reasons for the feasibility of the combined movement of high-speed passenger and freight trains. The research includes the analysis and theoretical synthesis of materials related to the combined movement of high-speed passenger and freight trains in European Union countries. The combination of different train categories on high-speed rail lines is not only possible but also, under certain conditions, advisable. The main reasons for arranging sections of combined passenger and freight movement include overcoming contour or height obstacles and justifying investments in the construction of high-speed railways where the demand for passenger transportation is insufficient and profitability is ensured through additional income from cargo transportation. The combined movement of high-speed passenger and freight trains can reduce environmental impact by ensuring the efficient use of railway infrastructure and decreasing transport emissions. The authors have proposed a comprehensive approach to assessing the effectiveness of implementing the movement of high-speed passenger and accelerated freight trains, considering the net present value and ensuring the capacity of the double-track railway line during concurrent train movements. The research results enable enhancing the stability of railway transportation on high-speed railways.
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.
Deformation Characterization of Glass Fiber and Carbon Fiber-Reinforced 3D Printing Filaments Using Digital Image Correlation
(MDPI, Basel, Switzerland, 2025) Nemes, Vivien; Szalai, Szabolcs; Szívós, Brigitta Fruzsina; Sysyn, Mykola; Kurhan, Dmytro; Fischer, Szabolcs
ENG: The paper offers an in-depth deformation study of glass fiber-reinforced and carbon composite filaments of 3D printers. During the certification, the authors used DIC (Digital Image Correlation) as a full-field strain measurement technique to explore key material traits as a non-contact optical measurement method. The insights captured through the DIC technology enabled to better understand the localized strain distributions during the loading of these reinforced filaments. The paper analyzes the glass fiber and carbon fiber filaments used in 3D printing that are reinforced with these materials and are subjected to bending and compressive loading. The segment presents how loading affects the performance of reinforced filaments when varying such factors as the deposition patterns, layer orientation, and other process parameters. Different types and combinations of reinforcements and printing variables were tested, and the resulting dependencies of mechanical parameters and failure modes were established for each case. Key conclusions demonstrate that the mechanical behavior of both carbon- and glass fiber-reinforced filaments is strongly affected by the 3D printing parameters, particularly infill density, pattern, and build orientation. The application of Digital Image Correlation (DIC) allowed for a precise, full-field analysis of strain distribution and deformation behavior, offering new insights into the structural performance of fiber-reinforced 3D printed composites. The findings from the study provide guidance for the proper choice of filling material and the optimal parameters for the 3D printing process of models with high-performance indexes and seamless applications in the automotive and industrial manufacturing sectors.
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.
Driver Distraction Detection in Extreme Conditions Using Kolmogorov–Arnold Networks
(MDPI, 2025) Hollósi, János; Kovács, Gábor; Sysyn, Mykola; Kurhan, Dmytro; Fischer, Szabolcs; Nagy, Viktor
ENG: Driver distraction can have severe safety consequences, particularly in public transportation. This paper presents a novel approach for detecting bus driver actions, such as mobile phone usage and interactions with passengers, using Kolmogorov–Arnold networks (KANs). The adversarial FGSM attack method was applied to assess the robustness of KANs in extreme driving conditions, like adverse weather, high-traffic situations, and bad visibility conditions. In this research, a custom dataset was used in collaboration with a partner company in the field of public transportation. This allows the efficiency of Kolmogorov–Arnold network solutions to be verified using real data. The results suggest that KANs can enhance driver distraction detection under challenging conditions, with improved resilience against adversarial attacks, particularly in low-complexity networks.
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.
Enhancing Railway Section Capacity, during Expansion of the European Railway Network
(Óbuda University. Budapest, Hungary, 2025) Kurhan, Mykola; Kurhan, Dmytro; Hmelevska, Nelya
ENG: The Trans-European Transport Network was established by the European Union to connect Europe from west to east and north to south through a transportation network. One of the challenges in organizing barrier-free railway connections across European countries is the varying track gauge. Some European countries continue to use gauges different from 1435 mm. The aim of this study is to provide a scientific justification for reconstruction options, for a railway section, taking into account technical, economic, and other aspects, as well as to develop recommendations for a successful transition to European track standards. In this work, the authors examined the Kovel-Sarny-Korosten section, which is part of the Warsaw-Kyiv route. This route is one of several options for upgrading to European gauge to create a continuous railway network between the European Union and Ukraine. The research methodology and scientific approaches may vary depending on the characteristics of the sections being considered. In this study, the authors implemented the following sequence of steps: determined the maximum freight capacity for each segment, assessed the existing capacity, analysed reconstruction measures, and evaluated the effectiveness of reconstruction options. The modernization of the railway corridor under consideration has significant potential to improve transport connectivity between Ukraine and Poland, as well as to stimulate economic development in the regions through which this route passes.
Entropy Application for Simulation the Ballast State as a Railway Element
(Óbuda University, Budapest, Hungary, 2023) Kurhan, Dmytro
ENG: The purpose of the paper is to develop methods of entropy application for simulation of the ballast layer operation of a railway track in the tasks of predicting and controlling the service life. The author developed a method for determining the entropy of the ballast layer as an element of a railway track through calculations of the mechanical work performed by ballast as a result of the reaction to an external load. To determine the array of stresses and deformations operating in the ballast layer space, the spatial model of the stress-strained state of a railway track based was used on the elastodynamic problem. The major part of the developed method is supplemented by the technique of assessing the entropy of a system according to the deviation measuring results in its geometric position. The geometric position of a railway track was measured by a track renewal train. Files archiving to determine the randomness of data recorded in them were carried out using the LZMA algorithm. The tasks of predicting and controlling the service life of ballast have been further developed. The usage of entropy has allowed simulating the ballast degradation as a random process that depends on cyclic stresses and deformations arising in ballast from rolling stock. For the first time, the method of assessing the quality of the track surfacing through the entropy of the ballast layer is proposed. The developed mathematical tool may be used to compare the service life of ballast in various operating conditions, which allows optimizing consistency between the track design and parameters of train movements.
Evaluating 3D-Printed Polylactic Acid (PLA)-Reinforced Materials: Mechanical Performance and Chemical Stability in Concrete Mediums
(MDPI, Basel, Switzerland, 2025) Csótár, Hanna; Szalai, Szabolcs; Kurhan, Dmytro; Sysyn, Mykola; Fischer, Szabolcs
ENG: The optimization and evaluation of 3D-printed polylactic acid (PLA) materials for reinforcing concrete elements present a promising avenue for advancing sustainable construction methods. This study addresses the challenges associated with PLA’s dual nature—biodegradable yet mechanically limited for long-term applications—while leveraging its potential to enhance concrete reinforcement. The research identifies gaps in understanding PLA’s mechanical and chemical behavior in alkaline environments, particularly its interactions with concrete matrices. To bridge this gap, four distinct PLA variants (high-impact PLA, engineering PLA, electrical ESD PLA, and gypsum PLA) and ABS (acrylonitrile butadiene styrene) were subjected to dissolution tests in NaOH solutions (pH 12 and 12.55) and mechanical evaluation under three-point bending using digital image correlation (DIC) technology. Test specimens were prepared using optimized 3D printing strategies to ensure structural consistency and were embedded in concrete beams to analyze their reinforcement potential. Force–displacement data and GOM ARAMIS measurements revealed significant differences in mechanical responses, with peak loads ranging from 0.812 kN (high-impact PLA) to 1.021 kN (electrical ESD PLA). Notably, electrical ESD PLA exhibited post-failure load-bearing capacity, highlighting its reinforcement capability. Chemical dissolution tests revealed material-specific degradation patterns, with high-impact and Gypsum PLA showing accelerated surface changes and precipitation phenomena. Observations indicated white crystalline precipitates, likely lime (calcium hydroxide—Ca(OH)2), residue from the dissolution tests (sodium hydroxide—NaOH), or material-derived residues formed on and near PLA elements, suggesting potential chemical interactions. These findings underline the critical role of material selection and optimization in achieving effective PLA–concrete integration. While PLA’s environmental sustainability aligns with industry goals, its structural reliability under long-term exposure remains a challenge. The study concludes that electrical ESD PLA demonstrates the highest potential for application in reinforced concrete, provided its chemical stability is managed, as its peak value (1.021 kN) showed 25.7% higher load-bearing capacity than high-impact PLA (0.812 kN) and did not lose any of its structural stability in the dissolution tests. This work advances the understanding of PLA as a sustainable alternative in construction, offering insights for future material innovations and applications.
Examination of Concrete Canvas under Quasi-Realistic Loading by Computed Tomography
(MDPI, 2023) Balázs, Eller; Movahedi, Rad M.; Fekete, Imre; Szalai, Szabolcs; Harrach, Dániel; Baranyai, Gusztáv; Kurhan, Dmytro ; Sysyn, Mykola; Fischer, Szabolcs
ENG: The current paper concerns the investigation of CC (Concrete Canvas), a unique building material from the GCCM (geosynthetic cementitious composite mat) product group. The material is suitable for trench lining, trench paving, or even military construction activities, while the authors’ purpose is to investigate the application of the material to road and railway substructure improvement. This research was carried out to verify the material’s suitability for transport infrastructure and its beneficial effects. The authors’ previous study reported that the primary measurements were puncture, compression, and the parameters evaluated in four-point bending (laboratory) tests. However, based on the results, finite element modeling was not feasible because the testing of the composite material in a single layer did not provide an accurate indication. For this reason, the material characteristics required for modeling were investigated. A unique, novel testing procedure and assembly were performed, wherein the material was loaded under quasi-realistic conditions with a crushed stone ballast sample and other continuous particle size distribution samples in a closed polyethylene tube. In addition, the deformation of the material following deformed bonding was measured by computed tomography scanning, and the results were evaluated.
Finite-Element Analysis of Strengthening the Subgrade on the Basis of Boring and Mixing Technology
(The Silesian University of Technology, 2021) Tiutkin, Oleksii L.; Neduzha, Larysa O.; Kalivoda, Jan
ENG: One of the effective techniques to strengthen the subgrade is boring and mixing technology, which is based on the immersion of vertical elements – piles into the subgrade. This method of strengthening significantly affects the stress state of the track superstructure. Two options of the placement of strengthening elements are examined in this paper. To determine the influence of position of strengthening elements on the stress state of the track superstructure, appropriate finite-element models were created. The models fully reflect the geometric and deformation characteristics of a real subgrade, which is strengthened by piles. The calculated stress state of the track superstructure is shown and analyzed in this paper. The main contribution of the paper lies in optimization of the geometric parameters of the technology to reduce the stress state of the "track superstructure–subgrade–soil basement" system. The results show that the location of piles near the rails is more effective than the location of piles near the ballast section.
Increasing the Efficiency of the Railway Operation in the Specialization of Directions for Freight and Passenger Transportation
(Obuda University, Hungary, 2022) Kurhan, Mykola ; Kurhan, Dmytro ; Husak, Marina ; Hmelevska, Nelya
ENG: It is shown that in the mixed traffic of trains compared to the directions specialized for transportation of freight and passengers, the traffic capacity is sharply reduced, and costs on repairs and maintenance of track infrastructure increase by 1.5-2 times. The paper outlines ways to solve the problem in the distribution of directions with mainly freight and passenger traffic to increase the traffic capacity of transportation on the rail network. Among the activities, there is the transmission of transit freight flow on parallel runs. Furthermore, changing the operation conditions of railways in the case of implementing the high-speed trains traffic requires strengthening the existing railway lines in the event of insufficient reserves.
The Influence of Geosyntetic Materials on the Strength in Uniaxial Compression of Soils of Railway Embasses
(Kaunas University of Technology, Kaunas, Lithuania, 2023) Andrieiev, Volodymyr S.; Tiutkin, Oleksii L.; Hubar, Oleksіy V.; Mukhina, Nataliya
ENG: Many specialists were engaged in ensuring the stability of the soils of the embankments of the railway track. Most of them propose to ensure the stability of embankments due to its reinforcement. There is a need to generalize and adapt individual features of different calculation methods in order to obtain a single calculation model of the system "embankment - reinforcing layer - base" and "base site - reinforcing layer - ballast layer". The operation of reinforcing layers depends on the type of soil, the type of reinforcing material, and the shape of the structure. Geotextile layers in embankments perform a reinforcing function. They are used to reinforce the embankment in order to increase the overall stability of the embankment and the local stability of the slopes. The reinforcing function is determined by the ability of the geotextile layer to improve the working conditions of the soil for displacement due to its perception of tensile forces, friction of the layer against the soil and changes in the stress state in the soil massif.
Innovative Approaches to Railway Track Alignment Optimization, in Curved Sections
(Óbuda University, Budapest, Hungary, 2024) Kurhan, Mykola; Kurhan, Dmytro; Hmelevska, Nelya
ENG: The efficient advancement of railway transportation is impossible without the integration of cutting-edge innovations. This study places emphasis on the application of computer modeling for railway track alignment, enabling the determination of an optimal strategy for rectifying curves within the plan. This approach ensures enhanced accuracy and effectiveness in curve realignment efforts. The calculations involved in plan correction are not only essential for addressing track deviations but also for solving a set of challenges associated with increasing permissible travel speeds. Particular significance is attributed to the reconstruction of track alignment, especially for international routes transitioning from wide (1520 mm) to standard European gauge (1435 mm). The incorporation of innovative technologies for railway curve correction, along with line plan optimization across multiple track sections, facilitates the realization of maximum stipulated velocities while ensuring safety, smoothness of motion, and passenger comfort. The investigation results detailed in this paper were conducted with support from a grant provided by The National Research Foundation of Ukraine under the project, "Scientific Justification of the Introduction of the European Track on the Territory of Ukraine in the Post-War Period".
Innovative Technologies for the Introduction of High-Speed Train Operation (on the Example of Track Maintenance in the Plan)
(Technologija, Kaunas, Lithuania, 2022) Kurhan, Mykola ; Kurhan, Dmytro ; Husak, Marina ; Hmelevska, Nelya
ENG: The purpose of the work is to research the process of introducing innovative technologies in the organization of highspeed train operations. The new knowledge is based on such scientific approaches as a comprehensive and detailed study of various aspects of innovative activities, which has provided an opportunity to increase the interoperability of the European transport system and recommend measures to organize high-speed train operations. The research used analysis methods to study the main directions in the introduction of innovative technologies and technical solutions in the field of, firstly, track infrastructure, scientific publications on the current state and trends in the European system of international railway transport, including innovative ways of development.
Investigation of “Open” Superstructure Tramway Tracks in Budapest
(2023) Jóvér, Vivien; Major, Zoltán; Németh, Attila; Kurhan, Dmytro ; Sysyn, Mykola; Fischer, Szabolcs
ENG: The most important thing nowadays is to use available resources to develop infrastructure as efficiently as possible. In this regard, evaluating the deterioration of tramway tracks is critical from both a technical and an economic viewpoint. In Hungary, seven types of superstructure systems are currently differentiated in the case of tramway transport, but the geometrical deterioration, lifecycle, and lifecycle cost of the tramway tracks are not accurately known. The current study aimed to evaluate and compare the results of track geometry measurements of two different “open” tramway superstructure systems depending on their traffic load and age. The geometry measurements we re executed by TrackScan 4.01 instrument, developed and maintained by a Hungarian developer company called Metalelektro Méréstechnika Ltd. The evaluation of the measurements showed a clear relationship between the traffic load, age, and track deterioration. Based on the results, it can be generally stated, concerning “open” superstructure systems, that regardless of the “open” superstructure system or the level of traffic load, the average value of alignment is decreasing; however, the average value of the longitudinal level is increasing. Furthermore, the deterioration of an older ballasted track with lower traffic is similar to that of a younger ballasted track that has a higher traffic load. Another significant result was that the deterioration of the track gauge parameter in the case of concrete slab tracks is clearly described as the broadening of the track gauge.
Investigation of Digital Light Processing-Based 3D Printing for Optimized Tooling in Automotive and Electronics Sheet Metal Forming
(MDPI, Basel, Switzerland, 2025) Szalai, Szabolcs; Szívós, Brigitta Fruzsina; Nemes, Vivien; Szabó, György; Kurhan, Dmytro; Sysyn, Mykola; Fischer, Szabolcs
ENG: This study addresses the emerging need for efficient and cost-effective solutions in low-volume production by exploring the mechanical performance and industrial feasibility of cutting tools that are fabricated using stereolithography apparatus (SLA) technology. SLA’s high-resolution capabilities make it suitable for creating precise cutting dies, which were tested on aluminum sheets (Al99.5, 0.3 mm, and AlMg3, 1.0 mm) under a 60-ton hydraulic press. Measurements using digital image correlation (DIC) revealed minimal wear and deformation, with tolerances consistently within IT 0.1 mm. The results demonstrated that SLA-printed tools perform comparably to conventional metal tools in cutting and bending operations, achieving similar surface quality and edge precision while significantly reducing the production time and cost. Despite some limitations in wear resistance, the findings highlight SLA technology’s potential for rapid prototyping and short-run manufacturing in the automotive and electronics sectors. This research fills a critical gap in understanding SLA-based tooling applications, offering insights into process optimization to enhance tool durability and broaden material compatibility. These advancements position SLA technology as a transformative tool-making technology for flexible manufacturing.
Investigation of FDM-Based 3D Printing for Optimized Tooling in Automotive and Electronics Sheet Metal Cutting
(MDPI, Basel, Switzerland, 2025) Szalai, Szabolcs; Szívós, Brigitta Fruzsina; Nemes, Vivien; Szabó, György; Kurhan, Dmytro; Sysyn, Mykola; Fischer, Szabolcs
ENG: Within the scope of the work, the possible use of fused deposition modeling (FDM) technology in executing rapid prototypes of cutting tools for aluminum sheets was systematically studied. Relevant investigations have thus far mainly concentrated on tools for the 3D printing of bent and deep-drawn pieces, yet the implementation of FDM tools in cutting has been insufficiently covered. This study aims to determine the characteristics of FDM cutting tools, such as wear and tear, dimensional stability, and cutting efficiency. Various tool designs were tested under different wall thicknesses and orientations with respect to the feed of Al99.5 sheets with thicknesses of 0.22 mm and 0.3 mm. According to the results, in the best case, three-dimensional printed PLA tools performed six cuts with no burrs and an acceptable wear level due to the IT tolerances (IT9 and IT10). Tools with thicker walls and more appropriate orientations were found to be more robust. However, some designs failed when subjected to greater loads, revealing a deficiency in some of the strength properties of the material. These observations suggest that it is possible to create 3D printed tools for modeling and small-scale production at considerably cheaper and faster rates than conventional methods. Future work will integrate advanced materials and designs to enhance tool performance, further solidifying FDM as a transformative approach in industrial tool manufacturing. With this research, the authors wanted to demonstrate that FDM technology can also be used to produce a classic sheet cut, which, of course, is still of great importance for prototyping or setting up production processes. This research demonstrated that FDM printing can play a role in this area.
Investigation of Heat-Affected Zones of Thermite Rail Weldings
(University of Niš, Republic of Serbia, 2024) Fischer, Szabolcs; Harangozó, Dóra; Németh, Dalma; Kocsis, Bence; Sysyn, Mykola; Kurhan, Dmytro; Brautigam, András
ENG: The paper investigates the heat-affected zone (HAZ) of several rail joints executed by thermite rail welding (TW). The examined rail profile was 54E1 (UIC54). The rail steel categories were different: R260 and R400HT. The welding portions of the TWs fitted R350HT and R260 rail categories with normal welding gaps. The rail pieces were brand new, i.e., without any usage in the railway track. The authors executed Vickers-hardness tests (HV10) and material texture tests on the running surface of the rail head, as well as on slices cut from the rail head. The cutting was performed by the water jet method, five longitudinal direction slices with vertical cutting lines. The considered specimen lengths were 2×70 mm (i.e., 70 mm from the mid-point of the rail joint), however, the depths were 20 mm from the running surface. Therefore, the measuring spaces were 5 mm lengthwise and 2 mm in depth. The variation of the hardness values was determined considering the microstructures of the base steel material and the TW. For comparison, previously measured Elektrothermit SoW-5 and earlier own research were taken into consideration.
Investigation of the Geometrical Deterioration of Paved Superstructure Tramway Tracks in Budapest (Hungary)
(MDPI, 2023) Jóvér, Vivien; Major, Zoltán; Németh, Attila; Kurhan, Dmytro; Sysyn, Mykola; Fischer, Szabolcs
ENG: In the 21st century, one of the key requirements is to develop and maintain our infrastructure facilities most efficiently using the available resources. Tramways are of significant national economic importance and represent an important national asset. There are currently seven different types of superstructure systems in Hungary, based on the national regulations and the related requirements currently in force. This paper compares the paved tramway superstructure systems in the context of track geometry, through-rolled axle tons of track, and the age of track sections. Paved tracks have many benefits, but the main ones are easier maintenance and road traffic use. Elastically supported continuous rail bedding (ESCRB; in Hungary, this is known as “RAFS”) and “large” slab superstructure systems are used to create paved superstructure systems. Road crossings use the latter systems, while heavily loaded lines use several ESCRB systems. This article examines the geometrical changes in several ESCRB superstructure systems. A TrackScan 4.01 instrument was used to take measurements in June and September 2021 and in April 2022, September 2022, and May 2023. Track gauge, alignment, and longitudinal level are examined. Regardless of the ESCRB superstructure system or age, a medium-loaded line’s track gauge trendline increases, which means that the track gauge is widening and, regardless of traffic load or age, the average longitudinal level is constantly increasing from year to year. When it is a medium-loaded line, the average value of alignment increases slightly, and the trendline is almost straight, but it decreases when it is an extremely heavily loaded line. The authors will analyze how the reference track section will change in the future. Based on the results, it is important to assess how subsequent measurements affect the trend lines. Because the data evaluations show similar results, comparing open tramway tracks to paved ones is crucial.
Laboratory and Numerical Investigation of Pre-Tensioned Reinforced Concrete Railway Sleepers Combined with Plastic Fiber Reinforcement
(MDPI, 2024) Németh, Attila; Ibrahim, Sarah Khaleel; Movahedi, Rad M.; Szalai, Szabolcs; Major, Zoltán; Kocsis Szürke, Szabolcs; Jóvér, Vivien; Sysyn, Mykola; Kurhan, Dmytro; Harrach, Dániel; Baranyai, Gusztáv; Fekete, Imre; Nagy, Richárd; Csótár, Hanna; Madarász, Klaudia; Pollák, András; Molnár, Bálint; Hermán, Bence; Kuczmann, Miklós; Gáspár, László; Fischer, Szabolcs
ENG: : This research investigates the application of plastic fiber reinforcement in pre-tensioned reinforced concrete railway sleepers, conducting an in-depth examination in both experimental and computational aspects. Utilizing 3-point bending tests and the GOM ARAMIS system for Digital Image Correlation, this study meticulously evaluates the structural responses and crack development in conventional and plastic fiber-reinforced sleepers under varying bending moments. Complementing these tests, the investigation employs ABAQUS’ advanced finite element modeling to enhance the analysis, ensuring precise calibration and validation of the numerical models. This dual approach comprehensively explains the mechanical behavior differences and stresses within the examined structures. The incorporation of plastic fibers not only demonstrates a significant improvement in mechanical strength and crack resistance but paves the way for advancements in railway sleeper technology. By shedding light on the enhanced durability and performance of reinforced concrete structures, this study makes a significant contribution to civil engineering materials science, highlighting the potential for innovative material applications in the construction industry.