Scoping Prediction of Railway Critical Velocity

D. P. Connolly, S. B. Mezher, P. K. Woodward, Z. Yu, O. Laghrouche, Joao Pombo, P. Alves Costa

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

When train speeds approach the wave propagation velocity of the supporting trackground system, track displacement amplitudes can increase significantly. This is undesirable and can cause both elevated maintenance and safety concerns. Thus, it is important to determine the speed at which these effects will occur, however modelling the problem in detail (e.g. using numerical techniques) can result in long run times. Therefore, as an alternative, this paper uses an analytical approach to investigate the dispersion characteristics of the track-ground system, and thus calculate the critical velocity. Unlike alternative approximate critical velocity calculation approaches, the proposed method is fully automated thus not requiring any post-processing to extract the soil dispersion curve. It has low computational requirements meaning it can be used quickly for large sections of track. After the model is outlined, it is validated against a larger, more comprehensive model and found to have high accuracy. A Monte Carlo analysis is then undertaken using 1000 random soil profiles. It is found that ballasted tracks typically have a lower critical velocity than slab tracks and that track height and soil saturation play an important role on the critical speed.

Original languageEnglish
Title of host publicationProceedings of the Third International Conference on Railway Technology
Subtitle of host publicationResearch, Development and Maintenance
EditorsJ. Pombo
PublisherCivil-Comp Press
ISBN (Print)9781905088652
DOIs
Publication statusPublished - Apr 2016
Externally publishedYes
EventThe Third International Conference on Railway Technology: Research, Development and Maintenance - Cagliari, Sardinia, Italy
Duration: 5 Apr 20168 Apr 2016
Conference number: 3
http://www.civil-comp.com/conf/rw2016/rw2016.htm (Link to Conference Website)

Publication series

NameCivil-Comp Proceedings
PublisherCivil-Comp Press
Volume110
ISSN (Print)1759-3433

Conference

ConferenceThe Third International Conference on Railway Technology
Abbreviated titleCCP
CountryItaly
CitySardinia
Period5/04/168/04/16
Internet address

Fingerprint

Soils
Wave propagation
Processing

Cite this

Connolly, D. P., Mezher, S. B., Woodward, P. K., Yu, Z., Laghrouche, O., Pombo, J., & Alves Costa, P. (2016). Scoping Prediction of Railway Critical Velocity. In J. Pombo (Ed.), Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance [1] (Civil-Comp Proceedings; Vol. 110). Civil-Comp Press. https://doi.org/10.4203/ccp.110.1
Connolly, D. P. ; Mezher, S. B. ; Woodward, P. K. ; Yu, Z. ; Laghrouche, O. ; Pombo, Joao ; Alves Costa, P. / Scoping Prediction of Railway Critical Velocity. Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance. editor / J. Pombo. Civil-Comp Press, 2016. (Civil-Comp Proceedings).
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Connolly, DP, Mezher, SB, Woodward, PK, Yu, Z, Laghrouche, O, Pombo, J & Alves Costa, P 2016, Scoping Prediction of Railway Critical Velocity. in J Pombo (ed.), Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance., 1, Civil-Comp Proceedings, vol. 110, Civil-Comp Press, The Third International Conference on Railway Technology, Sardinia, Italy, 5/04/16. https://doi.org/10.4203/ccp.110.1

Scoping Prediction of Railway Critical Velocity. / Connolly, D. P.; Mezher, S. B.; Woodward, P. K.; Yu, Z.; Laghrouche, O.; Pombo, Joao; Alves Costa, P.

Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance. ed. / J. Pombo. Civil-Comp Press, 2016. 1 (Civil-Comp Proceedings; Vol. 110).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Connolly DP, Mezher SB, Woodward PK, Yu Z, Laghrouche O, Pombo J et al. Scoping Prediction of Railway Critical Velocity. In Pombo J, editor, Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance. Civil-Comp Press. 2016. 1. (Civil-Comp Proceedings). https://doi.org/10.4203/ccp.110.1