Навчально-науковий центр "Мости та тунелі" (раніше Факультет "Мости і тунелі") ДІІТ

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EN: Educational and Scientific Center (Faculty "Bridges and Tunnels") DIIT

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Actual Problems of Interaction of Objects of the Infrastructure and Rolling Stock
(Transcomp – XV International Conference, 2011) Kulyabko, Vladimir V.; Raspopov, Oleksandr S.; Artyomov, Vitaliy Y.; Artomov, Vitalii Y.; Artyomow, V. E.
EN: There are a number of actual problems of modern bridge construction in a context of static-dynamic interaction of bridge designs and the railway rolling stock is considered. The integrated classification of settlement models for research of joint dynamics of system "bridge-train" is offered, the basic criteria and the factors influencing result of numerical modeling and dynamic calculation of bridges are allocated.
Analysis of Deformed State Structures of the Kyiv Metro Running Tunnels on a Transition Zone from Spondylov’s Clay to Buchatskiy Sands
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2014) Petrenko, Volodymyr D.; Huzchenko, Victor T.; Tiutkin, Oleksii L.; Tiutkin, Dmytro V.
ENG: Purpose. In the section of changes geotechnical conditions of spondylov’s clay to buchatskiy sands may have significant structural deformation of running tunnels. It is necessary to identify the cause of deformities develop ways to minimize and based modeling and calculations to prove the effectiveness of measures to reduce deformation. Methodology. To solve the analysis problem of the stress-strain state (SSS) of the system «structure array» it was conducted the numerical simulation using the finite element method (FEM). On the basis of the obtained results the graphs were constructed and the dependencies were determined. Findings. The presence of weak watersaturated soils in tray of the tunnel on an area of transition from spondylov’s clay to buchatskiy sand causes significant increasing in strain construction of tunnels and general vibration liquefaction in soil basis. Also change the physical and mechanical characteristics of soils within the frames of tunnels influences on the level of strain state of most frames. Improved strain state settings of tunnels in areas of change soil characteristics of the array (especially at the bottom of casing) can be achieved by chemical consolidation of weak soils. Composition of solutions for fixing the weak soils should be determined based on the study of grain size, porosity, and other parameters of physical and mechanical and physical and chemical characteristics of soils. Originality. The basic cause significant strain on transition zone from spondylov’s clay to buchatskiy sands is found, that is explained by saturated phenomenon vibration liquefaction basis under the tunnel. Practical value. The approaches to reduce the strain in the construction of running tunnels in the transition zone from spondylov’s clay to buchatskiy sands are developed, as well as in the area of the station «Glybochytska» the Kyiv Metro.
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.
Analysis of the Differences of the Results of Calculations of the Stability Coefficient of the Landslide Slope
(Дніпровський національний університет залізничного транспорту ім. В. Лазаряна, Дніпро, 2019) Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Ihnatenko, Dmytro Yu.
ENG: Purpose. Improving the accuracy of determining the stability of landslide slopes in some cases requires the use of several methods to find the coefficient of stability. Therefore, it is necessary to analyze the discrepancy between the results of the calculation of the coefficient of stability of landslide slopes. Methodology. The solution to the problem of finite element slope modeling in the LIRA-SAPR 2016 software package is based on the creation of a spatial finite element model. With its help, the nonlinear problem of geomechanics was solved with the introduction of special finite elements, which simulates the work of the soil. As a reference, the coefficient of stability was calculated by the round-cylindrical sliding surface method. Landslide slope in the software package «OTKOS» was creat-ed and calculated. Results. The results of the calculation of the finite element model of the landslide slope in the LIRA-SAPR 2016 software package were obtained. The value of the coefficient of stability of the landslide-hazardous section of the slope in the «OTKOS» was obtained using eight methods. The calculation results in the «OTKOS» are compared with the coefficient of stability determined by the method of a circular-cylindrical sliding surface. Originality. The results of the calculation of the coefficients of stability in the «OTKOS» allowed us to divide the curves of the sliding surface into two groups: that which do not belong to circular-cylindrical, and that which satisfy the results of finite element modeling. Practical value. After a series of calculations and after analyzing the results, it turned out that not all methods equally solve the problem of the stability of landslide slopes. This is due to the different limitations of each of the methods, so as a criterion for the adequacy of the results obtained, it is necessary to analyze the magnitude of the discrepancy between the obtained values of the coefficient of stability.
Analysis of the Problems of Sections With the Transitional Rigidity Indicator in World Bridging
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Marochka, Vitalii V.; Boboshko, Stepan H.
EN: Purpose. To analyze the problem of areas with a transitional stiffness on the approaches to the bridges based on the experience of European and American bridge-building. To find out the root causes and methods for detecting track defects in transitional stiffness zones. To propose a pilot model for the development of transitional stiffness areas based on the experience of developed countries in Europe. Methodology. Collection of data on the causes and nature of the occurrence of bumps on approaches to bridges based on the experience of specialists in the design, construction and operation of railway and highway bridges. Analysis of methods of arrangement of transition areas on approaches to bridges in European countries. Results. An analysis of the literary sources of developed countries of the world on the problem of the origin and methods of detection of bumps in areas with transitional stiffness on the approaches of bridges was performed. The results were collected on ways to identify problems in areas with transient stiffness and how to solve them. A model for mathematical and experimental studies was proposed. Origi-nality. Scientific interest is that, despite the extensive experience of developed countries of the world, the Ukrainian norms still do not have a clear mechanism for identifying and characterizing problems of track geometry in sections with transitional stiffness. Thus, studying the experience of more advanced countries in the field helps to con-sider the problem more clearly and standardize its definition. Practical value. If proposed model of reinforcement of transition stiffness areas will be confirmed it allows to reduce the cost of maintaining of the track and to solve the problems of the transitional areas at the stage of bridge construction, that is, before its immediate occurrence.
Application of Centrifugal Modeling for the Study of Landscape Structure Stability
(Tamilnadu, India, 2019) Ignatenko, D. Yu.; Tiutkin, Oleksii L.; Petrenko, Volodymyr D.; Alkhdour, Ahmad M.
ENG: The calculation of stability by mathematical methods of complex shapes of slopes with a diverse geological structure is reduced to simple formulations and assumptions for finding curves of sliding surfaces and for forecasting possible forms of stability loss. The method of centrifugal modeling allows us to conduct in-depth studies of the experimental, reproduced, reduced scale of the slope and to reliably identify the nature of the existing deformations after rotation on a centrifuge, analyze them and draw conclusions about the stability of the studied slope. The centrifugal simulation can be divided into four stages, each of which is described in detail in this article with reference to photo materials and descriptions. The obtained results of the centrifugal modeling of the shifting slope of the Krasnopovstanska ravine and the analysis of the deformed state of the model before and after placement of soil cement piles in the body of the slope. Centrifugal modeling is not a new method for studying the stability of slopes. This method requires special complex hardware and hardware, therefore, it is used rather infrequently. Conducting this type of research is accompanied by a small amount of informative literature on the methodology of the simulation itself. This article is devoted to the question of conducting and successfully using the method of centrifugal modeling of landslide slopes with the observance of certain features. Application of the technique of centrifugal modeling allows solving problems of calculating the stability of natural slopes with complex geological structure
The Application of Injection - Grouting for Strengthening of the Weak Subgrade Foundations
(PGASA, 2014) Petrenko, Volodymyr D.; Sviatko, Ilona O.; Yampolskyy, D. O.
ENG: This article analyzes the features of the subgrade construction on soft soils, and offers to use injection–grouting technology, which is widely used abroad, but needs official regulations for the application in observed area.
The Application of Injection - Grouting for Strengthening of the Weak Subgrade Foundations (preprint)
(PGASA, 2014) Petrenko, Volodymyr D.; Sviatko, Ilona O.; Yampolskyy, D. O.
ENG: This article analyzes the features of the subgrade construction on soft soils, and offers to use injection–grouting technology, which is widely used abroad, but needs official regulations for the application in observed area.
The Basing of Stabilization Parameters of a Fortified Railway Bed
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2015) Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Kulazhenko, O. M.; Alkhdour, Ahmad M.
ENG: Purpose. The article is devoted to stabilization parameters determination of reinforced railway bed. At the present time, the railway plays the leading role in transport system to ensure the needs of freight and passenger traffic. In modern conditions railway operation concentrates on ensuring the necessary level of track reliability, including the roadbed, this is one of the main elements of road structures. The purpose of this article is the determination of basic parameters of stress-strain state to stabilize the soil subgrade embankment by reinforced materials. Methodology. To achieve this goal the following tasks of researches were solved: the effect of reinforcing layer of geomaterial on deformation properties of soil subgrade in various design of strengthening was investigated, the distributions of stresses in the subgrade were determined, reinforced of geomaterials under state load. Experimental studies to explore the nature of the deformation model subgrade at various degrees of stress were carried out. Findings. The analysis of the results of performed experimental and theoretical studies permitted to do the following conclusions. In conducting researches determined the distribution of stresses in the subgrade reinforced geomaterials under static load. The complex of experimental studies allows exploring the nature of the deformation model subgrade at various degrees of stress. Originality. On the basis of the theoretical studies have been regarded the problem of determining the stress-strain state of subgrade reinforced geomaterials by measuring stresses in its application for step loads. Practical value. The practical value was presented by the results of evaluating the effect of reinforcing way for changing the stress-strain state of subgrade.
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 Calculation Results of Supporting Structure of Soil-Cement Piles
(Kaunas University of Technology, Kaunas, 2019) Pshinko, Oleksandr M.; Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Andrieiev, Volodymyr S.; Hubar, Oleksіy V.; Ihnatenko, Dmytro Yu.; Markul, Ruslan V.
ENG: Abstract. The article presents the results of comparison of the stress-strain state of 4 models of a retaining wall structure of soil-cement piles on a landslide-prone slope. This study compares the changes in the stress distribution and displacements in the model elements of the retaining structure of soil-cement piles depending on the design parameters and the method of piles location in the body of the soil mass. The comparison of models of supporting structures of soil-cement piles on a landslide-prone slope allowed obtaining: –the comparative analysis of the quality work of individual elements of the supporting structure for strength and deformation in a three-dimensional representation; –the comparative assessment of the performance of the supporting structure of soil-cement piles on a landslide-prone slope; – histograms of dependences of changes in the angle of piles inclination to the vertical axis of their holding force, strength and deformation of the slope;
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 Parameters of the Strength of the Subgrade at the Transition to the Higher Axial Loading up to 25 t
(IOP Publishing, Kharkiv, 2019) Radkevych, Anatolii V.; Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Andrieiev, Volodymyr S.; Mukhina, Nataliya
ENG: Abstract. A review of the scientific and technical literature on the re-alignment of the route during the transition to high axial load from the accepted today (23.5 t / axis) to the perspective (25 t / axis) shows that in the stage of preliminary researches imitation modeling of the earth web by the finite element method (ITU) as the most convenient, accurate and illustrative of the known numerical methods. In order to provide recommendations on the strength of the subgrade when moving to a higher axial load up to 25 t / axis, an analysis was conducted, the essence of which was to compare the stress-strain state of the subgrade at two loads per axis: 23.5 t / axis (existing ) and 25 (perspective). All the geometric and deformation characteristics of the formation are taken from data on a two-track section with a height of embankment of 3. The deformation characteristics are chosen so that the working material of the formation is in accordance with the average indices of deformation capacity of the railways used. The ITU train load calculus makes it possible to obtain all the factors of VAT in it, which is the main purpose of the study of the strength of the earth cloth, and allows to forecast their development in the future.
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.
Comparative Calculation of the Stability of the Landslide Slope in the Software Complexes «OTKOS» and «LIRA-CAD 2017»
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2018) Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Ihnatenko, Dmytro Yu.; Kovalchuk, Vitalii V.
ENG: Purpose. The analysis and comparison of the results of calculation by the finite-element model of the slope in the software complex «LIRA-CAD 2017» with the determination of the its stability in the software complex «OTKOS» allows to determine the accuracy the results and the most favorable conditions for the development of the displacement and parameters of the most dangerous surface slip for further calculation of anti-slip retaining structures. Methodology. The geomorphological data were obtained from the results of laboratory studies of soils in the considered slope. Creation of a bulk finite element model of the slope in accordance with the built cuts and depths of soil layers. Calculation of the nonlinear problem of finite-element simulation of the slope in the software complex «LIRA-CAD 2017». Creation and calculation of the stability problem of the landslide slope in the software complex «OTKOS» and comparison of the results of the its stress-strain state. Results. The results of calculating the finite-element model of the landslide slope in the software complex «LIRA-CAD 2017» and its stability in the software complex «OTKOS» were obtained. The analysis of the obtained results of sliding surfaces study is carried out. The calculation of the strengthening of the slope area is carried out with the help of soil cement retaining piles, located at right angles to the vector of the displacement direction. Originality. Despite the presence of a large number of different methods of studying the surfaces of sliding, it is impossible to determine exactly the scenario of the displacement, using only one of the calculation methods. First of all, this is due to the rather high variation of the initial data of the problem, which in turn depends on the environment and assumptions, as well as on external factors that can not be taken into account precisely. The next task is to carry out the calculation of the strengthening of the landslide slope by soil-cement piles. Practical value. It is known that it is advisable to use soil-cement piles as a protective element, which interacts well with the soil environment due to its structure of the source material. A comparative analysis of the calculation results of the slope stability with the help of software systems «LIRA-CAD 2017» and «OTKOS» gives an answer to the question of the its reliability.
Complex Analysis of Subgrade Stress-Strain State with Combined Strengthening
(Полтавський національний технічний університет імені Юрія Кондратюка, Полтава, 2017) Petrenko, Volodymyr D.; Tiutkin, Oleksii L.; Sviatko, Ilona O.; Alhdur, A. M. M.
ENG: The paper highlights combined techniques of strengthening that include geotextile laying as well as other related advanced technologies. Subgrade construction analysis and its modification, reinforced with the different types and options of combined strengthening were conducted. To justify strengthening of subgrade a series of numerical calculations were made. Simulation with software package SCAD has confirmed the experimental results. From obtained results one can conclude that minimum horizontal displacements are observed in the version with deepening of geotextile at 1m and vertical ones at 0.4 m. Based on simulation results it is possible to make recommendations concerning modernization of existing subgrade and construction of new one in complex engineering-geological conditions.
Comprehensive Analysis of the Retaining Pile Structure with the Determining the Stability Factor by Numerical Methods
(EDP Sciences, 2019) Dubinchyk, Olha I.; Petrenko, Volodymyr D.; Ihnatenko, Dmytro Yu.; Kildieiev, Vitalii R.
EN: Abstract. The paper highlights the results of the complex analysis of the retaining pile structure with determining the stability coefficient by numerical methods. To achieve this purpose, after designing a structure with jet grouting piles, the research of the stability coefficients of the landslide hazard slopes in the software complex "OTKOS" and its stress state in the software complex LIRA-CAD system was conducted. The relevance of the completed research is to develop rational parameters of the pile structure. A comparison of determining the stability coefficient of a slope by different methods for the existing landslide stretch for the public roadways of local significance С141017 (Lviv-Shehyni) – Sudova Vyshnia was carried out. Originality of the paper lies in the fact that to determine the stability coefficient in the model, the layeredness of the slope under study is taken into account, and the nonlinear volumetric problem is solved in the course of the numerical analysis of the stress state. The rational distance between piles in the gap and the length of the pile under a certain percentage of cement and ground was justified.