Hat Esneme Direncinin Hat Performansı Üzerindeki Etkileri

Bir demiryolu hattının sahip olması gereken esneme direnci değeri, hattın güvenli hizmet vermesini sağlamakla birlikte hattın bakım maliyetini de azaltacak şekilde belirlenmelidir. Hattın geometrik özelliklerini korumak için hat esneme direnç değerinin yüksek olması istendiği gibi, uygun yük dağılımını sağlamak ve hat bileşenlerinin yıpranmasını önlemek amacıyla bu değerin azaltılması gerekir. Bir bütün olarak hattan en fazla verimin alınabilmesi için en uygun esneme direnci değerinin seçilmesi gerekir. Bu değerin seçiminde, esneme direncinin hat performansını etkileyen ray sehimleri, basınç ve gerilmeler gibi unsurlar üzerindeki etkileri göz önünde bulundurulmalıdır.Bu çalışmada hat esneme direncinin değişmesiyle hat performansını etkileyen parametrelerin değişimi incelenmiştir. Çok yüksek ve çok düşük esneme direnci değerleri altında karşılaşılan sorunlar ele alınmıştır. Böylece en yüksek güvenlik, en az bakım maliyeti ve en uzun hizmet ömrünü sağlayan bir esneme direnç değeri seçilmesinin önemi ortaya konulmuştur. Son olarak, belirlenen esneme direnci değerinin uygulamada sağlanabilmesi için yapılan çalışmalara yer verilmiştir.

The Effects of Track Stiffness on Track Performance

Required stiffness value for a railway track must determined within the safety limits and it should reduce maintenance costs. While track must be stiff enough to conserve track’s geometric qualities, it must also provide sufficient flexibility in order to provide proper load distribution and avoid wear in track components. While determining this value, effects of the track stiffness on the track design parameters that influence track performance such as track deformations, pressure and strains must be taken into consideration.

___

[1] G. Sauvage and J. Fortin, “La traînee de roulement des vehicles de chemin de fer,” Rev. Gen. Chemins Fer, pp. 383–390, 1982.

[2] B. Lichtberger, Track Compendium. Hamburg, Germany: Eurail Press, 2005.

[3] W. Powrie and L. Le Pen, A Guide to Track Stiffness. Southampton, UK: University of Southampton, 2016.

[4] M. Burrow, P. Teixeira, T. Dahlberg, and E. Berggren, “Track stiffness considerations for high speed railway lines, “Railway transportation: policies, technology and perspectives,” pp. 303–354, 2009.

[5] N.Ö. Bezgin, “Development of a New and an Explicit Analytical Equation that Estimates the Vertical Dynamic Impact Loads of a Moving Train” Procedia Engineering Volume 189, 2017, Pages 2-10

[6] M. Wehbi and P. Musgrave, “Optimisation of track stiffness on the UK Railways,” Permanent Way Institute Journal, pp. 135, 2017.

[7] E. Berggren, “Railway track stiffness. Dynamic measurements and evaluation for efficient maintenance,” Ph.D. dissertation, KTH Royal Institute of Technology, Stockholm, 2009.

[8] C. Kolukırık and N.Ö. Bezgin, “Demiryolu taşıt tekerleklerinde oluşabilen geometrik kusurlar nedeniyle meydana gelen dinamik darbe yüklerinin tahmini için yeni bir yöntem,” 7. Geoteknik Sempozyumu, İstanbul, Turkey, 2017.

[9] N.Ö. Bezgin, M. Wehbi “Advancement and Application of the Bezgin Method to Estimate Effects of Stiffness Variations along Railways on Wheel Forces” Transportation Research Record, Volume: 2673 issue: 7, page(s): 248-264. 2019.

[10] O. Şahin, “Demiryolunda hat rijitliğinin ve etkilerinin incelenmesi,” M.Sc. dissertation, İstanbul Technical University, İstanbul, 2011.

[11] C. Aron and E. Jonas, “Structural element approaches for soil-structure interaction,” M.Sc. dissertation, Chalmers University of Technology, Göteborg, 2012.

[12] L. Puzavac, Z. Popović, and L. Lazarević, “Influence of track stiffness on track behaviour under vertical load,” PROMET - Traffic&Transportation, no. 24, pp. 405–412, 2012.

[13] B. McVey, C. Norman, N. Wood, S. Farritor, R. Arnold, M. Fateh, and M. El-Sibaie, “Track Modulus Measurement From A Moving Railcar,” Proceedings of the AREMA 2005 Annual Conference, Chicago, IL, 2005.

[14] E. Balcı, “Demiryollarında esneklik değişimlerinin düşey tekerlek kuvvetleri üzerindeki etkilerinin incelenmesi” M.Sc. dissertation, İstanbul Üni.-Cerrahpaşa, İstanbul, 2019.

[15] J. Ringsberg, “Prediction of fatigue crack initiation for rolling contact fatigue,” International Journal of Fatigue, no. 22(3), pp. 205–215, 2000.

[16] Y. Sato, “Study on high-frequency vibration in track operated with high-speed train,” Q. Rep. Railway Tech. Res. Inst. (RTRI), no. 18(3), pp. 63–76, 1977.

[17] V.A. Diyaljee, “Effects of stress history on ballast deformation”, Journal of Geotechnical Engineering, no. 113(8), pp. 909–914, 1987.

[18] A.L. Pita, P.F. Teixeira, and F. Robuste, “High speed and track deterioration: The role of vertical stiffness of the track,” Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, no. 218(1), pp. 31–40, 2004.

[19] A.D. Kerr, Fundamentals of railway track engineering. Omaha, Nebraska: Simmons-Boardman Books, 2003.

[20] A.F. Bower, “The Influence of Crack Face Friction and Trapped Fluid on Surface Initiated Rolling Contact Fatigue Cracks,” Journal of Tribology, no. 110(4), 1988.

[21] P.E. Bold, M.W. Brown, and R.J. Allen, “Shear mode crack growth and rolling contact fatigue,” Wear, no. 144(1-2), pp. 307–317, 1991.

[22] V. Arlı, Demiryolu Mühendisliği (genişletilmiş 2. baskı). İstanbul: Birsen Yayınevi, 2015.

[23] H. Ilias, “The influence of railpad stiffness on wheelset/track interaction and corrugation growth,” Journal of Sound and Vibration, no. 227(5), pp. 935–948, 1999.

[24] J.I. Egana, J. Vinolas, and M. Seco, “Investigation of the influence of rail pad stiffness on rail corrugation on a transit system,” Wear, no. 261(2), pp. 21, 2006.

[25] A. Remennikov, S. Kaewunruen, and K. Ikaunieks, “Deterioration of dynamic rail pad characteristics,” Conference on Railway Engineering, Melbourne, Australia, 2006, pp. 173-179.

[26] P. Schneider, R. Bolmsvik, and J.C.O. Nielsen, “In situ performance of a ballasted railway track with under sleeper pads,” Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, no. 225(3), pp. 299–309, 2011.

[27] A. Riessberger, “Ballast track for high speeds,” Proceedings "Tracks for High-Speed Railways", Porto, Portugal, 2006, pp. 23-44.

[28] S. Witt, “The Influence of Under Sleeper Pads on Railway Track Dynamics,” Proceedings of Linköping University, Division of Solid Mechanics, 2008.

[29] A. Johansson, J.C.O. Nielsen, R. Bolmsvik, A.Karlström, and R. Lundén, “Under sleeper pads—Influence on dynamic train–track interaction,” Wear, no. 265(9-10), pp. 1479–1487, 2008.

[30] J. Ali Zakeri, M. Esmaeili, and H. Heydari-Noghabi, “A field investigation into the effect of under sleeper pads on the reduction of railway-induced ground-borne vibrations,” Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, no. 230(3), pp. 999–1005, 2016.

[31] P.K. Woodward, J. Kennedy, O. Laghrouche, D.P. Connolly, and G. Medero, “Study of railway track stiffness modification by polyurethane reinforcement of the ballast,” Transportation Geotechnics, no. 1(4), pp. 214–224, 2014.