scholarly journals Elastic characteristics of the underrail base of a ballastless railway track

2021 ◽  
Vol 2021 (4) ◽  
pp. 469-479
Author(s):  
Alexey F. KOLOS ◽  
◽  
Ksenia I. IVANOVA ◽  
Keyword(s):  
Practical Importance ◽  
Operating Conditions ◽  
Railway Track ◽  
Rolling Stock ◽  
Relative Stiffness ◽  
Ballastless Track ◽  
Full Scale Tests ◽  
The Impact ◽  
Track Modulus ◽  
Elastic Characteristics

Objective: Experimental determination track modulus and the coeffi cient of relative stiffness of underrail base and the rail, which are the main elastic characteristics that determine the stresses in the structural elements of track superstructure under the impact force from the train. The values of these parameters for a track with a ballast layer are well studied, in contrast to a ballastless track. Comparison of the elastic characteristics of a ballastless railway track with analogs of a track on ballast, as well as an assessment of their effect on the stress-strain state of the superstructure elements of a ballastless track. Methods: When carrying out full-scale tests, strain-gauge methods for measuring stresses in the elements of the track superstructure were used. The obtained values were processed by the methods of mathematical statistics. One statistical series included the values of stresses corresponding to one type of rolling stock, fi xed axle load and train speed, changing by no more than 10 km/h. The probability level in processing the results was taken in all cases equal to 0,994. Results: The values of track modulus and the coeffi cient of the relative stiffness of the underrail base and the rail were obtained for a ballastless structure of the RHEDA 2000 type. Practical importance: The results allow us to consider the rail as a beam lying on a solid elastic foundation in relation to the ballastless track and use the existing calculation methods for the design of ballastless track structures depending on the operating conditions.

The development of service conditions for special-purpose cars based on the results of full-scale tests

2018 ◽  
pp. 455-462
Author(s):  
Dmitriy Arshintsev ◽  
Sergey Tolmachev ◽  
Alexander Brzhezovskiy
Keyword(s):  
Practical Importance ◽  
Full Scale ◽  
Rolling Stock ◽  
Normative Documents ◽  
Regulatory Documents ◽  
Loading Mode ◽  
Multiple Unit ◽  
Service Conditions ◽  
Full Scale Tests ◽  
The Impact

Objective: To develop the conditions of special cargo railway cars, multi-axis container cars and railway non-autonomous multiple unit trains circulation for transportation of special-purpose goods on public railways of OAO “RZhD”. The speeds of such trains can be higher in comparison with the speeds established by the existing normative documents of JSC “Russian Railways” for cargo trains. Special-purpose cars in nominal loading mode circulate in a train set with a unit locomotive. Methods: The assessment of conditions of the special-purpose rolling stock circulation was carried out by the results of tests on the line as well as the impact on the track and pointwork in the accredited centers, based on the regulations of GOST R 55050–2012. Results: The conditions for the fleet circulation consisting of 8–32-axle special-purpose railway cars, multiaxial container cars and non-autonomous multiple unit trains were established. Practical importance: A set of regulatory documents of JSC “Russian Railways” was developed in the form of regulations on technical conditions of special-purpose railway cars, conveyors and multiple unit trains designed for transportation of special purpose freight.

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.

MODELLING THE INTERACTION BETWEEN RAILWAY WHEEL AND RAIL

Transport ◽  
2008 ◽  
Vol 23 (3) ◽  
pp. 236-239 ◽  
Author(s):  
Stasys Dailydka ◽  
Leonas Povilas Lingaitis ◽  
Sergey Myamlin ◽  
Vladimir Prichodko
Keyword(s):  
Mathematical Model ◽  
Operating Conditions ◽  
Rolling Stock ◽  
Dynamic Processes ◽  
Running Speed ◽  
Railway Wheel ◽  
The Real ◽  
The Impact ◽  
Railway Rolling Stock

The article presents a mathematical model for assessing the real operating conditions of railway rolling stock, taking into account the situations when the wheel loses contact with rail. The obtained amplitudinal fluctuation characteristics depend on the set roughness function and the running speed of the wheel. When calculating dynamic processes, the contact between wheel and rail should be considered unstable. With the increase of speed, the impact of this instability increases.

scholarly journals Railway Track Stress–Strain Analysis Using High-Precision Accelerometers

2021 ◽  
Vol 11 (24) ◽  
pp. 11908
Author(s):  
Alexandr Avsievich ◽  
Vladimir Avsievich ◽  
Nikita Avsievich ◽  
Dmitry Ovchinnikov ◽  
Anton Ivaschenko
Keyword(s):  
High Precision ◽  
Strain Analysis ◽  
Railway Track ◽  
Rolling Stock ◽  
Mathematical Methods ◽  
Stress Strain ◽  
Technical Parameters ◽  
The Impact ◽  
The Internet Of Things ◽  
Track Line

We propose a new approach for railway path diagnostics on the basis of track line stress–strain analysis using the data provided by high-precision accelerometers. This type of sensor provides sufficient accuracy with lower costs, and enables the development of a railway digital twin, according to the concept of the Internet of Things. The installation of sensors on a railway track along its entire length allows real-time monitoring of the states of the technical parameters of the railway track, and using mathematical methods to evaluate its wear on the basis of constantly received data. This paper presents an original 3D model of a railway track line and the results of its analysis using a finite element method. To test the model, we performed an analysis of the normal stresses and deformations in the elements of a railway track by simulating the impact of rolling stock on a section of a railway track with intermediate rail fastenings, ZhBR-65SH. The research results were probated and tested at the testing ground of the Kuibyshev branch of Russian Railways, the Samara track. The proposed approach makes it possible to determine the load of the track, and knowing the movement of the rail, to calculate the structural stress in the elements of the railway track, to constantly monitor the parameters of the slope and rail subsidence.

Utilization factor of adhesive weight of a locomotive with group tractive engine drive of wheelsets

2017 ◽  
pp. 267-279
Author(s):  
Victor Kruchek ◽  
Aleksander Grishenko ◽  
Tamila Tytova
Keyword(s):  
Mathematical Model ◽  
Power Transmission ◽  
Characteristic Curve ◽  
Practical Importance ◽  
Analytical Calculation ◽  
Operating Conditions ◽  
Railway Track ◽  
Movement Speed ◽  
Power Equipment ◽  
Utilization Factor

Objective: To improve accuracy of analytical calculation of adhesive weight of constructed and newly projected locomotives with wheelset group tractive drive. To bring out analytical dependence of a locomotive’s adhesive weight usage coefficient from a number of wheelsets in a group tractive engine considering constructive features of a vehicle, operating conditions and power equipment cycle of operation. Methods: Analytical dependences and a mathematical model were obtained on the basis of higher mathematics, laws of theoretical mechanics, reliability theory, probability theory, wheel-rail adhesion theory and the laws of self-excited frictional oscillations during slippage. Results: Mathematical model was developed to determine the highest value of a twisting moment, in the process of which occurs different slippage of a wheelset group tractive drive of a locomotive, taking into account the stochastic character of wheel-rail adhesion, shaking at the moment of starting and in the process of running. Characteristic curve of equalizing factor was plotted from a generalized parameter of a locomotive tractive drive. Practical importance: Analytical dependences make it possible to identify the right adhesive weight of a locomotive with wheelset group tractive drive for conducting traction calculations and the assessment of locomotive’s tractive capacity in the process of operation on different cycles of power equipment and movement speed. The level of dynamic load on group tractive drive components was determined, taking into account constructive features of trucks and power transmission, such as the jet thrust location of wheelset axial gear units, as well as maintenance conditions – movement speed and irregularities of a railway track. The results of the study may be applied in projecting the new and constructed locomotives.

COMPARATIVE ANALYSIS OF THE RESULTS OF FORCE IMPACT ON THE TRACK WITH APPLICATION OF SCHLUMPF, “RZhD-2016” AND “NVTs-TKP” METHODS

2017 ◽  
pp. 174-189
Author(s):  
Anton Petrov ◽  
Kirill Yeliseyev ◽  
Alexander Tretyakov ◽  
Alexander Marykyn ◽  
Victor Nikityn ◽  
...  
Keyword(s):  
Strain Gauge ◽  
Dynamic Testing ◽  
Practical Importance ◽  
Direct Methods ◽  
Rolling Stock ◽  
Dynamic Tests ◽  
Data Logging ◽  
Continuous Record ◽  
Force Impact ◽  
The Impact

Objective: To improve the integrity of running and dynamic testing results of force impact on the track, on the basis of modern facilities of data logging and wireless transmission from rotary elements of a car, as well as the change from indirect to direct methods of measurement. Methods: Comparative running and dynamic tests of the impact on the track were held simultaneously on the same section of the track, using three methods of logging vertical and side forces, that is Schlumpf (State Standard R 55050-2012), “RZhD-2016” and “NVTs-TKP” methods. The key difference of the third method was the application of strain-gauge set of wheels (TKP), making it possible to keep a continuous record of forces acting in the “wheel-rail” system throughout the track, whereas other methods allowed for the realization of the above mentioned only on districts with a limited amount of sections. Results: According to the results of comparative testing, a conclusion was made on the improvement of integrity and justification of the method of “NVTs-TKP” with an application of strain-gauge set of wheels. Practical importance: It was suggested to apply “NVTs-TKP” method to implementing organizations of running and dynamic tests when evaluating the load of an innovative rolling stock on the track.

scholarly journals Influence of the axial loads of rolling stock on the contact-fatigue life of rails

2018 ◽  
Vol 77 (3) ◽  
pp. 149-156 ◽  
Author(s):  
V. S. Kossov ◽  
G. M. Volokhov ◽  
O. G. Krasnov ◽  
M. N. Ovechnikov ◽  
A. L. Protopopov ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Service Life ◽  
Contact Fatigue ◽  
Calculated Data ◽  
Operating Conditions ◽  
Rolling Stock ◽  
Axial Loads ◽  
Rolling Surface ◽  
Contact Fatigue Life ◽  
The Impact

Analysis of operational data for defective and highly defective rails showed that up to 25 % is the contact-fatigue defects. In connection with the development of heavy haul traffic on the Russian railways, it is relevant to determine the influence of cars with increased axial loads of 25 and 27 tf on the contact fatigue life of rails. The solution of this problem is set forth in this article. The Brown-Miller model of multi-axial fatigue was used in the calculation. This model is integrated into the Fatigue software system, which is tied to the Marc calculation system through Pat-ran. Since under operating conditions the wheel moves (rolls) along the rail on meandering trajectory, in computer modeling weight coefficients were taken into account that characterize the percentage of wheels in the cross-sectional areas of the rail. Calculations of contact fatigue life took into account the variability of vertical loads from the impact on the track of trains formed from innovative open cars with axial loads of 23.5, 25 and 27 tf under operating conditions, loaded with real loading blocks. According to the analysis of calculated data with an increase in axial loads from 23.5 to 25 tf, it is necessary to expect a decrease in the service life of rails in contact fatigue resistance by 19 %, with a further increase in axle loads of up to 27 tf per 32 %. Considering that the share of freight cars with axial loads of 25 tf does not exceed 15...20 %, then on the routes of its use the service life of rails should be expected to decrease by 3...4 %. The method proposed by the authors for predicting the contact fatigue life of rails with increasing axial loads is advisable to improve in part of the experimental determination of the fatigue and strength characteristics of rail steel from the degree of hardening of the rolling surface, its probabilistic properties and the use of the integral distribution law for vertical forces, taking into account the structure of the freight traffic passing through the section. The work was carried out according to the RFBR project 17-20 01088.

scholarly journals Determination of natural frequencies of railway track elements under train load and selection of resilient shock absorbers

2021 ◽  
Vol 2021 (4) ◽  
pp. 57-64
Author(s):  
Аnastasiya А. КОNОN ◽  
Keyword(s):  
Traffic Safety ◽  
Natural Frequencies ◽  
Practical Importance ◽  
Physical Models ◽  
Railway Track ◽  
Rolling Stock ◽  
Oscillatory Process ◽  
Shock Absorbers ◽  
Force Impact ◽  
Absorbing Elements

Objective: To outline the theoretical and methodological foundations of the railway track oscillation frequency analysis. To justify the need to assess the level of vibrodynamic impact of rolling stock on the elements of the track superstructure and the roadbed. To provide a methodology for calculating the oscillation parameters. To evaluate the effectiveness of the use of shock-absorbing elements. Methods: The modeling of the oscillatory process of the railway track elements and the analysis of physical models of oscillations were used. Results: The applicability of assessing the level of vibrodynamic impact of rolling stock on the elements of the track superstructure and the roadbed has been confirmed. A physical model of the vibrodynamic force impact of railway rolling stock and the responses of track infrastructure elements is described. The procedure for calculating the natural frequencies of the elements of the track superstructure and the roadbed and the characteristics of the shock-absorbing elements is given. Practical importance: The presented methods for calculating the natural frequencies of the elements of the track superstructure and the roadbed, as well as the characteristics of resilient shock-absorbing elements – rail shock pads and sleeper pads – make it possible to evaluate the effectiveness of their use to reduce the level of vibrodynamic impacts, to protect against resonance, and ensure the train traffic safety.

Field Investigations on Rolling Stock Components Designed to Overcome Low Adhesion Related Problems

2010 ◽  
Author(s):  
Oscar Arias-Cuevas ◽  
Zili Li
Keyword(s):  
Friction Coefficient ◽  
Normal Load ◽  
Tangential Force ◽  
Operating Conditions ◽  
Rolling Stock ◽  
Field Investigations ◽  
Normal Traction ◽  
Multiple Unit ◽  
Fallen Leaves ◽  
Full Scale Tests

The tangential force that a braking or tractive wheel can exert on a rail is limited by the friction coefficient available at the surfaces in contact for a given normal load. In clean steel-on-steel contacts the friction coefficient is known to be higher than the adhesion requirements of the majority of the existent rolling stock. However, in the presence of contamination (e.g. leaves, water, grease, and rust) the friction level can decrease to values far below those required in normal traction and braking operations. In particular, fallen leaves have been identified by many railways to cause considerable low adhesion problems in autumn. Despite the available countermeasures the adhesion problems still seem to persist in the majority of the affected networks. This could to a large extent be due to the lack of fundamental understanding on the effectiveness of the countermeasures used under different operating conditions. In this paper, the effectiveness of two rolling stock components, namely locomotive sanders and permanent magnetic track brakes, in leaf contaminated contacts is investigated by means of full-scale tests in a stabling yard. An electrical locomotive has been used to asses the performance of the sanders, whereas the tests with permanent magnetic track brakes have been carried out with an electrical multiple unit.

Sign in / Sign up

Export Citation Format

Share Document