1212 Analysis on High Frequency Vibration Characteristic of Passenger-Seat in High Speed Railway Vehicle

The cement and asphalt mortar (CA mortar) used in the China Railway Track System (CRTS) I ballastless slab track may encounter a coupling fatigue effect under the high-frequency vibration, load and high-and-low temperature cycles, and the deterioration under fatigue may happen during service of the high-speed railway. In this study, the performance degradation and its mechanism of the CA mortar with and without polymer emulsion incorporated under the coupling fatigue effects of the high-frequency vibration, load and temperature were studied by using an anti-fatigue testing device specially developed for the CA mortar used in the ballastless slab track of the high-speed railway. The results showed that the deformation capacity of the CA mortar for CRTS I slab ballastless slab track decreased after fatigue test under simulated service environment, presenting a typical brittle characteristic and an obvious reduction of the ductility and toughness. The Scanning Electron Microscopy (SEM) observation and the mercury intrusion porosimetry (MIP) analysis showed that the volume of the macropore decreased whereas that of the micropore increased after the fatigue test. The asphalt in the hardened CA mortar revealed a softening and migration from the bulk paste to fill the pore and make the structure denser and even ooze out of the CA mortar under the high-frequency vibration and high temperature. Through incorporating the polymer emulsion, the anti-fatigue property of the CA mortar was obviously improved, which can prevent the CA mortar from losing its elastic adjustment function too early. Though increase of the strength and elastic modulus for the CA mortar after severe service is beneficial to the stability of train running, the comfort level and safety of the train operation may decline due to the gradual reduction of the ductility & toughness and the gradual loss of the elastic damping adjustment function of the CA mortar between the base concrete slab and the track slab.

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Vibration and Ride Comfort Analysis by Using Passenger-Seat Dynamics Models in High Speed Railway Vehicle

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.79.3177 ◽

2013 ◽

Vol 79 (805) ◽

pp. 3177-3191 ◽

Cited By ~ 3

Author(s):

Sotaro SAITO ◽

Pongsathorn RAKSINCHAROENSAK ◽

Masao NAGAI ◽

Ryuzo HAYASHI ◽

Ryohei SHIMAMUNE ◽

...

Keyword(s):

High Speed ◽

Ride Comfort ◽

Railway Vehicle ◽

High Speed Railway ◽

Passenger Seat ◽

Dynamics Models

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On the Crosswind Stability of High Speed Railway Vehicles

Rail Transportation ◽

10.1115/imece2006-13644 ◽

2006 ◽

Cited By ~ 2

Author(s):

Christian Wetzel ◽

Carsten Proppe

Keyword(s):

High Frequency ◽

High Speed ◽

Probabilistic Methods ◽

Railway Vehicle ◽

Uniform Rule ◽

High Speed Railway ◽

Railway Vehicles ◽

Turbulent Fluctuations ◽

Crosswind Stability ◽

The Given

The crosswind stability against overturning is a major design criterium for high speed railway vehicles. Due to the increasing interoperability in Europe it has also become an important international task. In recent years efforts have been made to derive an uniform rule in certifying railway vehicles. In this case especially probabilistic methods have been proposed These probabilistic techniques are common design criteria for wind turbines. A sophisticated method to compute the reliability of railway vehicles under strong crosswind is presented. In consideration of the given gust signal and the high-frequency turbulent fluctuations of the wind the response of a simplified train model is computed. The major failure criterion to determine the reliability is the lowest wheel-rail contact force of the railway vehicle. Special attention is given to the stochastic modeling of the high-frequency turbulent fluctuations of the wind and to the effect of these fluctuations on the crosswind stability.

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Research on Bogie Frame Lateral Instability of High-Speed Railway Vehicle

Shock and Vibration ◽

10.1155/2018/8469143 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13

Author(s):

Chen Wang ◽

Shihui Luo ◽

Ziqiang Xu ◽

Chang Gao ◽

Weihua Ma

Keyword(s):

High Speed ◽

Dynamics Simulation ◽

Lateral Acceleration ◽

Railway Vehicle ◽

Lateral Instability ◽

Bogie Frame ◽

High Speed Railway ◽

Long Time ◽

Line Test ◽

Equivalent Conicity

In order to find out the reason for the bogie frame instability alarm in the high-speed railway vehicle, the influence of wheel tread profile of the unstable vehicle was investigated. By means of wheel-rail contact analysis and dynamics simulation, the effect of tread wear on the bogie frame lateral stability was studied. The result indicates that the concave wear of tread is gradually aggravated with the increase of operation mileage; meanwhile the wheel-rail equivalent conicity also increases. For the rail which has not been grinded for a long time, the wear of gauge corner and wide-worn zone is relatively severe; the matching equivalent conicity is 0.31-0.4 between the worn rail and the concave-worn-tread wheel set. The equivalent conicity between the grinded rail and the concave-worn tread is below 0.25; the equivalent conicities are always below 0.1 between the reprofiled wheel set and various rails. The result of the line test indicates that the lateral acceleration of bogie frame corresponding to the worn wheel-rail can reach 8.5m/s2, and the acceleration after the grinding is reduced below 4.5m/s2. By dynamics simulation, it turns out that the unreasonable wheel-rail matching relationship is the major cause of the bogie frame lateral alarm. With the tread-concave wear being aggravated, the equivalent conicity of wheel-rail matching constantly increases, which leads to the bogie frame lateral instability and then the frame instability alarm.

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Modelling and evaluation of the hunting behaviour of a high-speed railway vehicle on curved track

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/0954409718789531 ◽

2018 ◽

Vol 233 (2) ◽

pp. 220-236 ◽

Cited By ~ 3

Author(s):

Vivek Kumar ◽

Vikas Rastogi ◽

PM Pathak

Keyword(s):

High Speed ◽

Degrees Of Freedom ◽

Critical Speed ◽

Transportation Network ◽

Graph Model ◽

Railway Vehicle ◽

Physical Damage ◽

Creep Theory ◽

High Speed Railway ◽

Hunting Behaviour

Nowadays, rail transport is a very important part of the transportation network for any countries. The demand for high operational speed makes hunting a very common instability problem in railway vehicles. Hunting leads to discomfort and causes physical damage to carriage components, such as wheels, rails, etc. The causes of instability and derailment should be identified and eliminated at the designing stage of a train to ensure its safe operation. In most of the earlier studies on hunting behaviour, a simplified model with a lower degree of freedom were considered, which resulted in incorrect results in some instances. In this study, a complete bond graph model of a railway vehicle with 31 degrees of freedom is presented to determine the response of a high-speed railway vehicle. For this purpose, two wheel–rail contacts grounded on a flange contact and Kalker’s linear creep theory are implemented. The model is simulated to observe the effects of suspension elements on the vehicle’s critical hunting velocity. It is observed that the critical hunting speed is extremely sensitive to the primary longitudinal and lateral springs. Other primary and secondary springs and dampers also affect the critical speed to some extent. However, the critical hunting velocity is insensitive to vertical suspension elements for both the primary and secondary suspensions. Also, the critical speed is found to be inversely related to the conicity of the wheel.

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Research into Correlation between the Lubrication Mode of Contact Surfaces and Dynamic Parameters of Turbo-Generator Transmissions

Advances in Materials Science and Engineering ◽

10.1155/2019/8148697 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Marek Kočiško ◽

Petr Baron ◽

Monika Telíšková ◽

Jozef Török ◽

Anna Bašistová

Keyword(s):

Acoustic Emission ◽

High Frequency ◽

High Speed ◽

Oil Quality ◽

The State ◽

Dynamic Parameters ◽

High Frequency Vibration ◽

Turbo Generator ◽

Friction Mode ◽

Contact Surfaces

The paper presents the results of an experimental study aimed at assessing the correlation between the measurement of dynamic parameters (vibration, high-frequency vibration, and acoustic emission) and the analysis of friction mode and the state of lubrication of the contact surfaces of two gearboxes in the turbo-generator assembly (high-speed single-body steam turbine—gearbox—generator) with the transmission power of no more than 50 MW. The analysis confirmed the assumption of a significant correlation of the monitored high-frequency vibration signal with the unsatisfactory engagement of the gear teeth. Through vibration analysis, an increased level of the tooth vibration component and vibration multiples with increased acoustic emission were identified in gearbox operation. The gear oil of one of the gearboxes examined showed a loss of additive elements in the real operation of the contact surfaces of the teeth engagement. The trend analysis confirmed the complexity of the monitored transmission operation in terms of the friction mode and the influence of the oil quality on the state of the tooth flank microgeometry.

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Improved backward fatigue statistical inference to the high-speed railway vehicle components

Procedia Structural Integrity ◽

10.1016/j.prostr.2020.01.027 ◽

2019 ◽

Vol 22 ◽

pp. 211-218

Author(s):

S.C. Wu ◽

C.H. Li ◽

G.Z. Kang ◽

L.Y. Xie ◽

W.H. Zhang

Keyword(s):

Statistical Inference ◽

High Speed ◽

Railway Vehicle ◽

High Speed Railway ◽

Vehicle Components

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Key Issues on Train Line Planning for Beijing-Shanghai High Speed Railway

2010 Joint Rail Conference, Volume 2 ◽

10.1115/jrc2010-36165 ◽

2010 ◽

Author(s):

L. Nie ◽

D. B. Fei ◽

S. D. Zhou ◽

H. L. Fu ◽

L. Tong

Keyword(s):

High Frequency ◽

High Speed ◽

Travel Demand ◽

Time Window ◽

Long Distance ◽

Line Planning ◽

High Speed Railway ◽

Passenger Flow ◽

Train Operation ◽

Service Plan

The Beijing-Shanghai High speed railway line (Hereinafter referred to as “Jing-Hu HSL”) is one of the most important railway lines in the Chinese rapid passenger transportation network and will be put into operation at the end of 2011. Train line planning directly reflects the quality and competition ability of train services. The characteristics of operational conditions and passenger flow of this corridor HSL bring about a few new issues on train line planning like night train operation, train OD sets, cyclic operation, and train stop schedule. For the first issue, a large amount of long distance travel demand put forward the demand for night services, which causes great conflict with the time-window for maintenance work. The confliction can be solved by harmoniously utilizing the parallel lines. For the second one, in view of the differences of technical and economic factors between HSL and conventional railways, high frequency and medium-long distance train will dominate HSL’s train service plan rather than low frequency and long distance trains on conventional railways. Thus, part of long-distance passenger flow has to transfer at some stations. Considering the whole possible ODs over Jing-Hu HSL and the transfer condition of related stations, the optimal OD sets and corresponding transfer plan is suggested. High frequency makes HSL possible to operate trains cyclically to improve service quality. However, with too many train ODs and some special trains, e.g. night train, an incomplete cyclic train operation mode is more practical. The ODs which can provide cyclic service for Jing-Hu HSL need to be identified. For the last issue, although non-stop long-distance train is a very popular kind of service in China, it should be reconsidered for Jing-Hu HSL line because of massive intercity travel demand and regular stops required. Each of the above issues is very complex. What is more, they have close relationship between each other. Due to limited space, the methods used to solve these issues are given in conceptual way rather than detailed description of mathematical model. The research paves the way for future integration study to design an efficient, economic, convenient, and regular train service plan for Jing-Hu HSL.

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