scholarly journals Static analysis of chosen imperfections of rail subgrade on additional rail deflection of contactless track

2016 ◽  
Vol 2016 (11) ◽  
pp. 34-46
Author(s):  
Włodzimierz Bednarek
Keyword(s):  
Theoretical Analysis ◽  
Static Analysis ◽  
Translational Motion ◽  
Compressive Force ◽  
Railway Track ◽  
Rolling Stock ◽  
Rail Track ◽  
Loss Of Contact ◽  
Rail Deflection

In the paper, the chosen imperfections of railway subgrade causing additional rail deflections in contactless tracks were analysed. For such imperfections the following problems were selected: contactless work of railway track resting on the local uneven subgrade; loss of contact between track and subgrade; influence of variable compressive force on the length of contactless track; change in support stiffness on the deflection of contactless rail track. The presented static analysis has shown the importance of unfavourable influence of selected factors on work of contactless rail track (e.g. increase in the length of contact loss between track and subgrade or arising an additional deflections and stresses). A special attention was paid on such imperfections, apart from deflections and stresses cause among other things a disturbance of translational motion of rolling stock due to these imperfections. In the paper, a special accent was laid on visualization the influence of selected factors on work of contactless rail track, giving in many places in the paper the proper publications, in which the complete procedures of theoretical analysis of the considered problems are shown in the comprehensive way.

scholarly journals Determination of the maximum dangerous width of a rail track on a reinforced concrete base with fasteners of the КБ type, taking into account all influencing factors

2021 ◽  
pp. 113-120
Author(s):  
Vadym Novikov ◽  
Andriy Babenko ◽  
Oleksandr Kharkivskyi ◽  
Olena Olexandrivna Tkachenko
Keyword(s):  
Reinforced Concrete ◽  
High Speed ◽  
Railway Track ◽  
Rolling Stock ◽  
Lateral Direction ◽  
Maximum Width ◽  
Rail Track ◽  
Emergency Braking ◽  
Simultaneous Influence

Railway track retention standards in Ukraine do not take into account theconstruction of the subrail base, but regulate one for all types maximum dangerous value of the trackwidth, which was changed from 1546 mm to 1548 mm without any justification of scientific researchor explanations of the effects of tolerances the width of the rail track and the wheel track, which ingeneral at that time were not fully investigated but taking into account the emergence anddevelopment of new scientific problems associated with the emergence of intensive lateral wear ofrails and ridges of locomotive and wagon wheels. The deterministic dependences of lateralimpressions of the P65 type rail thread head on the simultaneous influence of vertical and horizontalforces for the newly installed repair profiles of UZ rolling stock on the basis of previously performedexperimental and theoretical studies were investigated. The results allow at this stage of research todetermine and calculate the practical values of the maximum dangerous width of the track, in whichthe subrail base consists of reinforced concrete sleepers and separate rail fasteners, which are usedboth on conventional highways with mixed traffic and on high-speed lines UZ.The article establishes the need to take into account new factors influencing the dangerouswidth of the rail track with intermediate rail fasteners of separate type depending on the load stress of sections and new repair profiles of rolling stock, as well as wear processes of intermediate railfasteners type KБ and its elements on the appearance of elastic backlash in the lateral direction fromthe influence of the guide wheels of the rolling stock. The recommended value of the maximum widthof the rail track for areas where service or emergency braking is applied - 1550 mm, taking intoaccount that the contact of the wheel and the rail is not at a point, but on an ellipse. The establishednorm of the maximum width of a rail track allows to define economic efficiency of introduction in theconditions of operation of a track in curved sections of a track of small radii with limited use of themaximum admissible lateral wear (15 mm) of a head of a rail thread provided that the normal-forcedentry of rolling stock carts.

scholarly journals Research of safety indicators of diesel train movement with two-stage spring suspension

2018 ◽  
Vol 234 ◽  
pp. 05003 ◽  
Author(s):  
Andriy Kuzyshyn ◽  
Andriy Batig ◽  
Sergei Kostritsa ◽  
Julia Sobolevska ◽  
Vitalii Kovalchuk ◽  
...  
Keyword(s):  
Traffic Safety ◽  
Motor Vehicle ◽  
Stability Margin ◽  
Accurate Method ◽  
Railway Track ◽  
Rolling Stock ◽  
Operational Parameters ◽  
Wheel Pair ◽  
Rail Track ◽  
Safety Parameters

The problem of the interaction of rolling stock with the rail track has been analyzed in the present paper. It has been established that in the process of transport science development a number of methods for determining the causes of wheel pairs derailment are developed, which, in a varying degree, take into account the peculiarities of their interaction. The problem of choosing the most accurate method for estimating the causes of rolling stock derailment becomes more complicated because of the lack of sufficient experimental data that would allow us to verify the adequacy of the models. The indicators of stability of the wheel against derailment, which are used on the railways of Ukraine and Europe, have been examined. Their dependences on the speed of movement were derived. It has been established that the increase of the speed of motion leads to the increase of the interaction power of the rolling stock with the rail track, which may, under certain operational parameters, provoke its derailment. As a result of the calculations, it has been shown that the use of norms for car design and calculation used on Ukrainian railways can lead to an inadequate estimation of traffic safety parameters, since it does not take into account the unevenness of the railway track. It has been established that the requirements of BS EN 14363: 2005 European norms are stricter in comparison with the norms for calculation and evaluation of the bearing elements strength and dynamic qualities of motor-vehicle rolling stock used on Ukrainian railways. A comparison of the experimentally and theoretically calculated values of the stability margin coefficient against wheel derailment of the first wheel pair of the diesel train car was carried out.

scholarly journals Railway crane platform stabilization system

2021 ◽  
Vol 80 (3) ◽  
pp. 160-167
Author(s):  
D. A. Potakhov
Keyword(s):  
Computer Aided Design ◽  
Physical Nature ◽  
Technical System ◽  
Railway Track ◽  
Rolling Stock ◽  
Design System ◽  
Stabilization System ◽  
Rotating Platform ◽  
Automatic Stabilization ◽  
Rail Track

When operating a railway crane in curved sections of the track, derailment of wheelsets of the crane bogies from the rail track when it is displaced during hanging on the outriggers, wheelset of the bogie missing the rail track after the work has been completed or the crane has been down from the outriggers, which significantly affects performance of loading and unloading operations. One of the reasons for the occurrence of such dangerous situations is the not strictly horizontal position of the non-rotating platform of the railway crane.Railway cranes are part of recovery trains designed to eliminate the consequences of rolling stock derailments. A priority for recovery trains is to reduce the time it takes to eliminate the consequences of traffic accidents, which can be achieved through the use of new or improved devices or methods.The article describes a system of automatic stabilization (leveling) of the platform of a railway crane (for example, EDK 500/1 crane type) when it moves in curved sections of the track (the motion of a railway crane at relatively low speeds (up to 50 km/h) is considered).In order to study the modernized technical system (a crane equipped with an automatic platform stabilization system), its mathematical simulation is carried out. At the initial stage, a solidstate digital model of a railway crane in combination with a section of a railway track is created in the SolidWorks computer-aided design system; developed solid model is translated into the Sim- Mechanics MATLAB environment. Further, in order to improve the adequacy of modeling, the developed dynamic model is being finalized by integrating MATLAB program libraries (SimMechanics, SimHydraulics, Fuzzy Logic Toolbox, etc.) to take into account the interaction of elements of different physical nature. Results of modeling modernized technical system are presented, which confirm the advisability of using the stabilization system on railway cranes when passing curved track sections.

Tribology of rail bogie

2018 ◽  
Vol 77 (4) ◽  
pp. 230-240
Author(s):  
D. P. Markov
Keyword(s):  
Contact Fatigue ◽  
Basic Element ◽  
Difficult Problem ◽  
Railway Track ◽  
Rolling Stock ◽  
Kinematic Parameters ◽  
Approximate Estimation ◽  
Railway Bogie ◽  
Classical Calculation

Railway bogie is the basic element that determines the force, kinematic, power and other parameters of the rolling stock, and its movement in the railway track has not been studied enough. Classical calculation of the kinematic and dynamic parameters of the bogie's motion with the determination of the position of its center of rotation, the instantaneous axes of rotation of wheelsets, the magnitudes and directions of all forces present a difficult problem even in quasi-static theory. The paper shows a simplified method that allows one to explain, within the limits of one article, the main kinematic and force parameters of the bogie movement (installation angles, clearance between the wheel flanges and side surfaces of the rails), wear and contact damage to the wheels and rails. Tribology of the railway bogie is an important part of transport tribology, the foundation of the theory of wheel-rail tribosystem, without which it is impossible to understand the mechanisms of catastrophic wear, derailments, contact fatigue, cohesion of wheels and rails. In the article basic questions are considered, without which it is impossible to analyze the movement of the bogie: physical foundations of wheel movement along the rail, types of relative motion of contacting bodies, tribological characteristics linking the force and kinematic parameters of the bogie. Kinematics and dynamics of a two-wheeled bogie-rail bicycle are analyzed instead of a single wheel and a wheelset, which makes it clearer and easier to explain how and what forces act on the bogie and how they affect on its position in the rail track. To calculate the motion parameters of a four-wheeled bogie, it is represented as two two-wheeled, moving each on its own rail. Connections between them are replaced by moments with respect to the point of contact between the flange of the guide wheel and the rail. This approach made it possible to give an approximate estimation of the main kinematic and force parameters of the motion of an ideal bogie (without axes skewing) in curves, to understand how the corners of the bogie installation and the gaps between the flanges of the wheels and rails vary when moving with different speeds, how wear and contact injuries arise and to give recommendations for their assessment and elimination.

Monitoring the technical condition of the railway track using the method of continuous recording of dynamic processes occurring due to the interaction between rolling stock and railway track

2021 ◽  
pp. 66-82
Author(s):  
Yuriy P. BORONENKO ◽  
◽  
Aleksandr V. TRET’YAKOV ◽  
Rustam V. RAKHIMOV ◽  
Mariya V. ZIMAKOVA ◽  
...  
Keyword(s):  
Practical Importance ◽  
Stability Margin ◽  
Technical Condition ◽  
Continuous Recording ◽  
Railway Track ◽  
Lateral Interaction ◽  
Rolling Stock ◽  
Monitoring Method ◽  
Wheel Pair ◽  
Interaction Forces

Objective: To develop the method to monitor the technical condition of the railway track. Me-thods: A strain-gauge wheel pair is used for continuous recording of vertical and lateral interaction forces in a dynamic wheel–rail system. Results: Stability margin factors of a wagon relative to de-railment have been determined and the defective (prone to derailment) sections of a railway track have been identified with the exact identification of their location (GPS coordinates) on the map using navigation devices. Practical importance: The developed monitoring method makes it possi-ble to promptly re¬gister and eliminate railway track defects

scholarly journals Results of theoretical and experimental studies on determining the coefficient of subgrade reaction of sleepers for the conditions of main railways with axial loads of 30-35 tons per axle

2018 ◽  
Vol 230 ◽  
pp. 01003
Author(s):  
Oleksandr Darenskiy ◽  
Eduard Bielikov ◽  
Olexii Dudin ◽  
Alina Zvierieva ◽  
Anatolii Oleshchenko
Keyword(s):  
Sustainable Development ◽  
Reinforced Concrete ◽  
Axial Load ◽  
Experimental Studies ◽  
Operating Conditions ◽  
Railway Track ◽  
Rolling Stock ◽  
Subgrade Reaction ◽  
Axial Loads ◽  
Interaction Dynamics

The article considers obtaining numerical values of the coefficient of subgrade reaction of wooden and reinforced concrete sleepers with axial loads up to 30-35 tons per axle. It has been concluded that using the rolling stock with axial loads of up to 35 tons per axle is necessary in order to ensure sustainable development of the railway complex. The performance of the railway track thus should be investigated in order to predict its operation in such conditions. Generally, such studies are performed using numerical methods. One of the parameters that are required for such calculations is the parameter which is commonly called the coefficient of subgrade reaction. Empirical dependencies of the coefficient of subgrade reaction of wooden and reinforced concrete sleepers on the axial load and on the operating conditions of the track have been obtained. The obtained results can be used in studies of the interaction dynamics of the track of main railways with rolling stock with axial loads of 30-35 tons per axle, which will give an opportunity to provide well-grounded recommendations on the rules for the arrangement and maintenance of the track in such conditions.

scholarly journals Rethinking rail track switches for fault tolerance and enhanced performance

2016 ◽  
Vol 231 (9) ◽  
pp. 1048-1065 ◽  
Author(s):  
Samuel D Bemment ◽  
Emma Ebinger ◽  
Roger M Goodall ◽  
Christopher P Ward ◽  
Roger Dixon
Keyword(s):  
Fault Tolerance ◽  
Railway Track ◽  
The Novel ◽  
Functional Requirements ◽  
Rail Track ◽  
Rail Network ◽  
Solution Generation ◽  
Switch Design ◽  
Novel Concept ◽  
Novel Design

Railway track switches, commonly referred to as ‘turnouts’ or ‘points,’ are a necessary element of any rail network. However, they often prove to be performance-limiting elements of networks. A novel concept for rail track switching has been developed as part of a UK research project with substantial industrial input. The concept is currently at the demonstrator phase, with a scale (384 mm) gauge unit operational in a laboratory. Details of the novel arrangement and concept are provided herein. This concept is considered as an advance on the state of the art. This paper also presents the work that took place to develop the concept. Novel contributions include the establishment of a formal set of functional requirements for railway track switching solutions, and a demonstration that the current solutions do not fully meet these requirements. The novel design meets the set of functional requirements for track switching solutions, in addition to offering several features that the current designs are unable to offer, in particular to enable multi-channel actuation and rail locking, and provide a degree of fault tolerance. This paper describes the design and operation of this switching concept, from requirements capture and solution generation through to the construction of the laboratory demonstrator. The novel concept is contrasted with the design and operation of the ‘traditional’ switch design. Conclusions to the work show that the novel concept meets all the functional requirements whilst exceeding the capabilities of the existing designs in most non-functional requirement areas.

scholarly journals Investigation of KPP-5 Rail Fastener Elastic Deformation

2018 ◽  
Vol 15 (4) ◽  
pp. 5815-5825
Author(s):  
R. V. Markul ◽  
N. P. Nastechik ◽  
V. V. Kovalchuk ◽  
Y. M. Hnativ
Keyword(s):  
Elastic Deformation ◽  
Railway Track ◽  
Pressing Force ◽  
Rail Track ◽  
Long Period ◽  
Rail Wear ◽  
Main Influence

For a long period of operation, a number of shortcomings have been identified in KPP-5 fastener that is mainly due to an intensive decrease of pressing force of the rail on sleepers. This leads to the appearance of frequent cases of track displacement and fastening elements failure. To verify such hypothesis, the process of power work of KPP-5 fastener during railway track operation was researched. The technique and practical means of controlling the power work of KPP-5 fastener are developed. The influence of various factors of the rail pressing force on the sleeper is determined. The main influence is conditioned by under-rail wear (50.4%). The obtained results made it possible to formulate recommendations for the improvement of KPP-5 fastener where the methodology and practical means of controlling the power work of KPP-5 fastener were proposed. At the same time, it allows increasing the reliability and safety of the rail track during the entire overhaul period.

scholarly journals ANALYTICAL DETERMINATION OF CRITERIA FOR SAFETY OF MOTION AT RAILWAY TRANSPORT

2018 ◽  
Vol 18 ◽  
pp. 444-454
Author(s):  
A. V. Batig
Keyword(s):  
Traffic Safety ◽  
Stability Margin ◽  
Rolling Stock ◽  
Analytical Determination ◽  
Method Of Calculation ◽  
Rail Track ◽  
Advantages And Disadvantages ◽  
European Experience ◽  
European Standards ◽  
The Stability

The research on rolling stock stability condition for derailment was carried out by many foreign and domestic scientists, each of them proposed its own methods and approaches to its calculation. Each of proposed methods and approaches has its advantages and disadvantages that are analyzed in detail. Besides the method of determining the stability margin coefficient for derailment of rolling stock is indicated in currently accepted norms for calculation and design of railcars track of 1520 mm, in European standards. However, calculations based on the norms that are used for railways track of 1520 mm do not give an opportunity to take into account the parameters of the rail track, namely the irregularities in both the vertical and horizontal planes that occur during operation. So, calculations of traffic safety criteria according to these standards do not allow to determine the effect of wear of wheel pairs and rail track. Moreover exceeding the permissible value of stability margin coefficient for derailment of rolling stock does not always lead to the rolling in of the wheel flange on the railhead. Because the ratio of vertical load to horizontal force can exceed the permissible value, but the gap between the wheel flange and the bar will not be exhausted. Check of stability conditions from a derailment of rolling stock on accepted by norms for model 11-286 car is executed. The basic lacks of the used method of calculation and ways of its improvement are resulted. Creation of mathematical models of railcars will allow to take into account main features of construction of running gears, wear of wheelsets, railtrack and determine the time when the gap between the wheel flange and the rail is exhausted (their dynamic interaction arises). We should also analyze the European experience in determining the criteria for traffic safety.

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