Method for determining design life of ballastless way

The problem of the scope of ballastless track superstructure (BTS) and its service life currently is urgent. Due to the high traffic density at the Test Loop of JSC "VNIIZhT" for a short period of time it is possible to get an idea of BTS service life with freight transport at a speed of 80 km/h and axle load of 23.5 tonnes per axle. For information on BTS service life in real conditions of high-speed up to 400 km/h and axle load to 18 tonnes it would takes several decades.To resolve this contradiction it is proposed to apply a new methodology for forecasting the estimated service life of BTS at actual high-speed traffic by the results of tests on Test Loop with using mathematical modeling.In the proposed model track vibrations are considered as vibrations of construction comprising of three endlessly long beams, the bottom of which is based on a modified Winkler base and the upper and middle rely on the elastic layer mainly having a base characteristics as Winkler base. For specific design of ballastless track it would be the rail, the concrete support plate (track concrete) and hydraulically bound layer (lean concrete) correspondingly.The calculation results are presented in the form of amplitude-frequency characteristics of the bending moments in the second layer of ballastless track structure. Given the fact that the amplitude-frequency characteristic is not dependent on the axial load, the calculations are made for the particular case when the values of the speed of 80 km/h and 300 km/h with the actual characteristics of the layers of ballastless track that is operated on the Test Loop of JSC "VNIIZhT".The proposed algorithm and methodology make it possible to transfer the results of observations of the processes of degradation of tested ballastless track design, obtained at the Test Loop (st. Scherbinka), on sections of network, where installation of track of this design for mixed transport is assumed. In the future, this technique allows taking into account changes in the area of operational factors, including the effect of increasing the axial load or speed of trains on the durability of track design.

ballastless track, service life, deflections, stresses, damageability, modeling, tests, speed, axle load

1. Savin A. V. Vybor konstruktsii puti dlya vysokoskorostnogo dvizheniya [Selecting track design for high-speed traffic]. Vestnik VNIIZhT [Vestnik of the Railway Research Institute], 2014, no. 1, pp. 55 – 59.

2. Kovalenko N. I., Zamukhovskiy A. V., Kovalenko A. N. Kriteriy vybora konstruktsiy puti dlya VSM [Selection criterion of railway track construction for the high-speed traffic]. Mir transporta [World of transport], 2013, no. 4, pp. 88 – 94.

3. Zamukhovskiy A. V. Perspektivy poligona bezballastnogo puti [Prospects for test site of ballastless track]. Mir transporta [World of transport], 2013, no. 3, pp. 168 – 172.

4. Zamukhovskiy A. V., Kopylenko V. A., Fridkin V. M. O tekhnikoekonomicheskoy tselesoobraznosti primeneniya zheleznodorozhnykh estakad vmesto vysokikh nasypey [On the technical and economic feasibility of railway overpasses instead of high embankments]. Transportnoe stroitel’stvo [Transport construction], 2012, no. 10, pp. 15 – 18. Method for determining design life of ballastless way A. Ya. KOGAN, A. V. SAVIN Joint Stock Company “Railway Research Institute” (JSC “VNIIZhT”), Moscow, 129626, Russia

5. Schilder R., Diederich D. Installation Quality of Slab Track – A Decisive Factor for Maintenance. RTR Special. Austria, July 2007, рp. 76 –78. Available at: URL: http://www.eurailpress.de/leseprobe/203/download/magazine.pdf (retrieved on 20.08.2016).

6. Zoeteman A., Esveld C. Evaluating track structures: Life Cycle Cost Analysis as a Structured Approach. Delft University of Technology. World Congress on Railway Research Tokyo, 1999, рp. 1 – 9. Available at URL: http://www.silvertipdesign.com/BR(Imperial)/[18]%20Paper%20WCRR99%20Tokyo.pdf (retrieved on 01.09.2016).

7. Kogan A. Ya., Baraboshin V. F., Gavrilov V. M. Kolebaniya pyatisloynoy balki na uprugom osnovanii pod deystviem podvizhnoy dinamicheskoy nagruzki [Vibrations of five-layer beam on an elastic foundation under the action of moving dynamic load]. Mekhanika deformiruemogo tela i raschet transportnykh sooruzheniy: mezhvuz. Sb. nauch. tr. [Mechanics of deformable body and the calculation of the transport facilities: Proc. of sci. works]. Novosibirsk, NIIZhT Publ., 1986, pp. 33 – 43.

8. Savin A. V., Brzhezovskiy A. M., Tret'yakov V. V., Smelyanskiy I. V., Tolmachev S.V. Issledovaniya bezballastnoy konstruktsii verkhnego stroeniya puti [Research of ballastless design of track superstructure]. Vestnik VNIIZhT [Vestnik of the Railway Research Institute], 2015, no. 6, pp. 23 – 32.

9. Muramoto K., Sekine E., Nakamura T. Roadbed Degradation Mechanism under Ballastless Track and Its Countermeasures. QR of RTRI, 2006, Vol. 47, no. 4, Nov., pp. 222 – 227. Available at URL: https://www.jstage.jst.go.jp/article/rtriqr/47/4/47_4_222/_pdf (retrieved on 13.09.2016).

10. Ando Katsutoshi, Sunaga Makoto, Aoki Hifumi, Haga Osamu Development of Slab Tracks for Hokuriku Shinkansen Line. QR of RTRI, 2001, Vol. 42, no. 1, Mar., pp. 35 – 41. Available at URL: https://www.jstage.jst.go.jp/article/rtriqr/42/1/42_1_35/_pdf (retrieved on 20.09.2016).

11. Takahashi T., Sekine E. Evaluation of Factors Contributing to Deterioration of Track-slab in Cold Areas. QR of RTRI, 2011, Vol. 52, no. 3, Aug., pp.149 – 155. Available at URL: https://www.jstage.jst.go.jp/article/rtriqr/52/3/52_3_149/_pdf (retrieved on 26.09.2016).

12. Kogan A. Ya., Levinzon M. A., Voytov I. O., Gavrilov V. M., Perel’shtein A. L. Vozdeystvie ekipazha na put' pri prostranstvennykh kolebaniyakh podvizhnogo sostava. Opisanie programmy [The impact of the carriage on track at spatial oscillations of the rolling stock. Program description].Informatsionnyy byulleten' VNTITsentr [Information bulletin of VNIITsentr]. Moscow, GOSFAP Publ., 1985, no. 4/67, 40 p.

13. Kogan A. Ya., Nikitin D. A., Poleshchyuk I. B. Kolebaniya puti pri vysokikh skorostyakh dvizheniya ekipazhey i udarnom vzaimodeystvii kolesa i rel'sa [Vibrations of the track at high speeds of carriages and impact interaction of wheel and rail]. Moscow, Intext Publ., 2007, 168 p.