Effect of track defects on vibration from high speed train

Kaynia, Amir M.; Park, Joonsang; Norén-Cosgriff, Karin

doi:10.1016/j.proeng.2017.09.551

Cited by 21 publications

(8 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During the passage of a train over a track, a source of ground vibration is related to the variability of the track and ground [46]. The track variability may create local stress concentration under the sleepers.…”

Section: Loss Of Stiffness At Subgrade Layermentioning

confidence: 99%

“…This could lead to a loss of stiffness under the sleeper and a soft soil formation in the subgrade layer. In the long-term, it may create a loss of contact between the ballast and the sleepers, so-called hanging sleepers [46]. If hanging sleepers are not detected at the right time, they may accelerate the track deterioration and cause more damage.…”

Section: Loss Of Stiffness At Subgrade Layermentioning

confidence: 99%

See 1 more Smart Citation

Railway Track Loss-of-Stiffness Detection Using Bogie Filtered Displacement Data Measured on a Passing Train

Malekjafarian

O’Brien

Quirke³

et al. 2021

Infrastructures

View full text Add to dashboard Cite

This paper presents an innovative numerical framework for railway track monitoring using acceleration measurements from sensors installed on a passenger train. A numerical model including a 10 degrees of freedom train passing over a three-layer track is employed. The bogie filtered displacement (BFD) is obtained from the bogie vertical acceleration using a numerical integration method and a band-pass filter. The BFD is compared to the filtered track longitudinal profile and can be seen to contain the main features of the track profile. This is also experimentally confirmed using field measurements where an in-service Irish Rail train was instrumented using inertial sensors. The proposed algorithm is employed to find the BFDs from the bogie accelerations. A track level survey was also undertaken to validate the measurements. It is shown that the BFDs from several passes are in good agreement with the surveyed profile. Finally, the BFDs are numerically used to find track defects such as hanging sleepers. The mean of the BFDs obtained from two populations of train passes over a healthy and a damaged track are employed to detect the loss of stiffness at the subgrade layer. The effect of the train forward speed variation and measurement noise are also investigated.

show abstract

Section: Loss Of Stiffness At Subgrade Layermentioning

confidence: 99%

Section: Loss Of Stiffness At Subgrade Layermentioning

confidence: 99%

Railway Track Loss-of-Stiffness Detection Using Bogie Filtered Displacement Data Measured on a Passing Train

Malekjafarian

O’Brien

Quirke³

et al. 2021

Infrastructures

View full text Add to dashboard Cite

show abstract

“…It was shown that the track support stiffness measured by FWD is decreased due to the hanging sleepers. The effects of hanging sleepers and that of locally deteriorated substructure is investigated it the study [17]. Two numerical solutions were used for the simulation of track-substructure-ground response: the frequency-domain solution using a combination of beam elements for the track and FEM model.…”

Section: Review Of the Literaturementioning

confidence: 99%

Mechanism of the Sleeper-Ballast Dynamic Impact in Void Zones

Sysyn¹,

Przybyłowicz²,

Nabochenko³

et al. 2021

Preprint

View full text Add to dashboard Cite

Unsupported sleepers or void zones in ballasted tracks are one of the most recent and frequent track failures. The void failures have the property of intensive development that, without timely maintenance measures, can cause the appearance of cost-expensive local instabilities like subgrade damages. The reason of the intensive void development lies in the mechanics of the sleeper and ballast bed interaction. The particularity of the interaction is a dynamic impact that occur due to void closure. Additionally, void zones cause inhomogeneous ballast pressure distribution between the void zone and fully supported neighbour zones. The present paper is devoted studying the mechanism of the sleeper-ballast dynamic impact in the void zone. The results of experimental in-situ measurements of rail deflections showed the significant impact accelerations in the zone even for light-weight slow vehicles. A simple 3-beam numerical model of track and rolling stock interaction has shown the similar to the experimental measurements dynamic interaction. Moreover, the model shows that the sleeper accelerations are more than 3 times higher than the corresponding wheel accelerations and the impact point appear before the wheel enters the impact point. The analysis of ballast loadings shows the specific impact behaviour in combination with the quasistatic part that is different for void and neighbour zones, which are characterised with high ballast pre-stressed conditions. The analysis of void sizes influence demonstrate that the impact loadings, wheel and sleeper maximal accelerations appear at certain void depth after which the values decrease. The ballast quasistatic loading analysis indicates more than twice increase of the ballast loading in neighbour zones for long voids and almost full quasistatic unloading for short length voids. However, the used imitation model cannot explain the nature of the dynamic impact. The mechanism of the void impact is clearly explained by the analytic solution using a simple clamped beam. A simplified analytical expression of the void impact velocity shows that it is linearly related to the wheel speed and loading. The comparison to the numerically simulated impact velocities shows a good agreement and the existence of the void depth with the maximal impact. An estimation of the long-term influences for the cases of normal sleeper loading, high ballast pre-stress and quasistatic loading in the neighbour zones and high impact inside the void are performed.

show abstract

“…Besides, defects can remarkably increase the vibration of the track structure under train load, leading to further deterioration of the track. 2 Therefore, it is necessary to study the dynamic properties of periodic track structures with defects.…”

Section: Introductionmentioning

confidence: 99%

Characteristics of defect states in periodic railway track structure

Yan

Zhao

Wang

2021

Journal of Low Frequency Noise, Vibration and Active Control

View full text Add to dashboard Cite

To overcome the ill-conditioned matrix problem of the traditional transfer matrix method, the Floquet transform method and supercell technology are used to study the defect states of the periodic track structure. By solving the equations of the supercell directly, the propagation characteristics of elastic waves in the track structure with defects are analyzed. The existence of defects destroys the periodicity of track structure, thus resulting in the formation of defect states within the band gaps. Moreover, the elastic wave is localized near the defect position at the frequency of the defect state. The formation mechanism of the defect state in track structure can be explained by the local resonance at the defect. With the expansion of the defect range, the number of local resonance modes that can be formed near the defect increases, thus generating multiple defect states. Furthermore, the defect state enhances the vibration of the structure adjacent to the defect. Therefore, the vibration transmission coefficient in a finite-length range can be used to detect the defect characteristics in the track structure, and the defect degree can be evaluated by the peak frequency of the vibration transmission coefficient within the band gap.

show abstract

Effect of track defects on vibration from high speed train

Cited by 21 publications

References 10 publications

Railway Track Loss-of-Stiffness Detection Using Bogie Filtered Displacement Data Measured on a Passing Train

Railway Track Loss-of-Stiffness Detection Using Bogie Filtered Displacement Data Measured on a Passing Train

Mechanism of the Sleeper-Ballast Dynamic Impact in Void Zones

Characteristics of defect states in periodic railway track structure

Contact Info

Product

Resources

About