Journal of the Korean Society for Railway (한국철도학회논문집)

The Korean Society for Railway (한국철도학회)
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Development of Permanent Deformation Prediction Model for Trackbed Foundation Materials based on Shear Strength Parameters

강화노반 쇄석재료의 전단강도특성을 고려한 영구변형예측모델 개발

  • Lim, Yujin (Department of Civil, Environmental and Railroad Engineering, PaiChai University) ;
  • Hwang, Jungkyu (Sedam E&C) ;
  • Cho, Hojin (Department of Civil, Environmental and Railroad Engineering, PaiChai University)
  • Received : 2012.09.11
  • Accepted : 2012.10.29
  • Published : 2012.12.31
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Abstract

Formation used as trackbed foundation for providing vertical bearing capacity onto rail foundation are composed of crushed stones usually with certain type of grain size distribution. Permanent deformation in trackbed foundation can be generated by increasing number of load repetition due to train traffic increases, causing track irregularity. In this study, a specially prepared trackbed foundation materials (M-40) used in Korea has been tested using a large repetitive triaxial compression apparatus in order to understand resilient and permanent deformation characteristics of the material. From these test results, resilient and permanent deformation characteristic are analyzed so that a permanent deformation model is developed which can consider number of load repetition N, confining stress (${\sigma}_3$), shear stress ratio(${\tau}/{\tau}_f$) and stiffness of the material.

궤도하부층의 지지강성을 확보하기 위하여 설치하는 강화노반은 통상 일정 입도분포의 쇄석재료로 구성된다. 이러한 강화노반은 통과톤수의 누증 즉, 과도한 열차하중이 반복적으로 가해질 경우 영구변형이 발생할 수 있으며 이러한 영구변형은 궤도틀림의 한 원인이 될 수 있다. 또한 강화노반 재료의 적정두께를 확정하기 위해서는 이러한 영구변형 특성을 파악하는 것이 중요하다. 본 연구에서는 국내 강화노반 재료로 사용될 가능성이 높은 M-40 쇄석재료를 선정하여 대형반복삼축시험을 실시하여 재료의 회복탄성 특성과 영구변형 특성을 분석하였다. 시험으로부터 임의 전단응력비 및 반복재하횟수에 따른 회복탄성계수 특성과 영구변형 발생특성을 분석하였으며 M-40 쇄석강화노반 재료의 영구변형에 영향을 미치는 인자(반복재하횟수, 구속압, 전단응력비, 탄성계수 등)를 함께 고려할 수 있는 영구변형 예측모델을 제시하였다.

Keywords

References

  1. D. Li, E. T. Selig (1998) Method for railroad track foundation design. I: development, J. Geotech. Geoenv. Eng., ASCE, 124(4), pp. 316-322. https://doi.org/10.1061/(ASCE)1090-0241(1998)124:4(316)
  2. UIC (1994) Earthworks and track-bed layers for railway lines. UIC Code 719R, International Union of Railways, Paris, France.
  3. D.L. Heath, M.J. Shenton, R.W. Sparrow, J.M. Waters (1972) Design of conventional rail track foundations, Proc. Inst. Civ. Eng., 51, pp.251-267. https://doi.org/10.1680/iicep.1972.5952
  4. E.C. Shin, H.S. Yang, C.Y. Choi (2008) Estimation of Reinforced Roadbed Thickness based on Experimental Equation, Proc. 2012 Spring Conf. Korean Society for Railways, pp. 1734-1742.
  5. R.D. Barksdale (1972) Laboratory evaluation of rutting in base course materials, Proc. 3rd Int. Conf. on the Structural Design of Asphalt Pavements, London.
  6. E.T. Selig, C.S. Chang (1981) Soil Failure Modes in Undrained Cyclic Loading, Journal of Geotechnical Eng. Division, ASCE, 107(GT5), pp. 539-551.
  7. P. Gräbe, C. Clayton (2009) Effects of Principal Stress Rotation on Permanent Deformation in Rail Track Foundations, J. Geotech. Geoenviron. Eng., 135(4), pp.555-565. https://doi.org/10.1061/(ASCE)1090-0241(2009)135:4(555)
  8. I.T. Kim (2005) Permanent deformation behavior of airport flexible pavement base and subbase courses, Ph.D. Dissertation, University of Illinois at Urbana-Champagne, USA.
  9. A.A. van Niekerk (2002) Mechanical behavior and performance of granular bases and sub-bases in pavement, PhD Thesis, Delft University of Technology, Delft.
  10. L.W. Cheung, A.R. Dawson (2002) Effects of Particle and Mix Characteristics on the Performance of some Granular Materials, Transportation Research Record, Transportation Research Board, pp. 90-98.
  11. L. Korkiala-Tanttu (2008) Calculation Method for Permanent Deformation of Unbound Pavement Materials, Ph.D. Dissertation, Department of Civil and Env. Engineering, Helsinki Univ. of Tech., Helsinki, Finland.
  12. N. Janbu (1963) Soil compressibility as determined by oedometer and triaxial tests, Proc. Euro. Conf. on Soil Mech. and Found. Engrg., German Society for Soil Mechanics and Foundation Engineering, Wissbaden, Germany, Vol. I, pp. 19-25.
  13. Y. S. Kim, D. M. Kim (2009) Evaluation for Applications of the Levenberg-Marquardt Algorithm in Geotechnical Engineering, Journal of Korean Geo-environmental Society, KGS, 10(5) , pp. 49-57.
  14. Hagan, M.T. (1996) Neural network design, 1st ed, PWS Pub., Boston.
  15. IBM (2010) SPSS: the Statistical Package for the Social Sciences program, USA.
  16. M. Sagong, D.H. Kim, C.Y. Choi (2008) Evaluation of the Resilient and Permanent Behaviors of Cohesive Soils, Journal of the Korean Society for Railway, 11(1), pp.61-68.

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  2. Evaluation of Resilient Modulus for Reinforced Trackbed using Large Triaxial Tests vol.17, pp.6, 2014, https://doi.org/10.7782/JKSR.2014.17.6.415