Dynamic performance of high-speed railway formation with the rise of water table

Abstract This paper presents an experimental study on the influences of water table and train speeds on the dynamic performance of high-speed railway formation using a full-scale physical model testing apparatus. Stationary cyclic loading tests were first conducted to assess the fundamental dynamic performance of railway formation caused by increasing groundwater table. Resilient deformation increased significantly when water table rose from the subsoil bottom to the subgrade surface, and the resonant frequency of the track-formation system decreased from 16 Hz to 12 Hz. Then moving loading tests simulating train's passages were performed to reveal the dynamic responses of railway formation at train speeds of 5–360 km/h, such as the resilient deformation, dynamic soil stress and dynamic pore water pressure. Test results of two kinds of subgrade conditions were presented and compared, i.e., the design condition with the optimum subgrade moisture content and the extreme condition of the submerged subgrade. Combined with the amplification effect of increasing train speeds, the dynamic responses developed faster and larger due to water table rising. The contact pressure distribution under the track structure exhibited the shape of concave parabola for the optimum subgrade, while the distribution pattern presented the shape of letter “W” for the submerged subgrade as the soils around the edges entered into the plastic state. Finally, determination of the subgrade thickness for the design and extreme conditions was discussed, and the design code underestimated the subgrade thickness for the extreme situation in high-speed railways.

[1]  William Powrie,et al.  Measurements of transient ground movements below a ballasted railway line , 2010 .

[2]  S F Brown,et al.  EFFECT OF MOISTURE ON THE STRUCTURAL PERFORMANCE OF A CRUSHED-LIMESTONE ROAD BASE , 1987 .

[3]  Hong-wei Huang,et al.  Laboratory Characterization of Fouled Railroad Ballast Behavior , 2009 .

[4]  Javad Sadeghi,et al.  INVESTIGATION ON THE ACCURACY OF THE CURRENT PRACTICES IN ANALYSIS OF RAILWAY TRACK CONCRETE SLEEPERS , 2005 .

[5]  Yunmin Chen,et al.  Numerical simulation of high-speed train induced ground vibrations using 2.5D finite element approach , 2008 .

[6]  K. Terzaghi,et al.  Soil mechanics in engineering practice , 1948 .

[7]  R C K Wong,et al.  In Situ Pore Pressure Responses of Native Peat and Soil Under Train Load: A Case Study , 2006 .

[8]  William Powrie,et al.  Determination of Dynamic Track Modulus from Measurement of Track Velocity during Train Passage , 2009 .

[9]  S. Pudasaini.  A general two-phase debris flow model , 2012 .

[10]  Changjie Xu,et al.  Steady state responses of poroelastic half-space soil medium to a moving rectangular load , 2007 .

[11]  Yuanqiang Cai,et al.  Response of railway track system on poroelastic half-space soil medium subjected to a moving train load , 2008 .

[12]  Yunmin Chen,et al.  Simulating train moving loads in physical model testing of railway infrastructure and its numerical calibration , 2016 .

[13]  L. Auersch,et al.  Dynamic Stiffness of Foundations on Inhomogeneous Soils for a Realistic Prediction of Vertical Building Resonance , 2008 .

[14]  William Powrie,et al.  Stress changes in the ground below ballasted railway track during train passage , 2007 .

[15]  Hirokazu Takemiya,et al.  Substructure Simulation of Inhomogeneous Track and Layered Ground Dynamic Interaction under Train Passage , 2005 .

[16]  Yunmin Chen,et al.  Full-scale model testing on a ballastless high-speed railway under simulated train moving loads , 2014 .

[17]  A R. Jumikis.  Theoretical Soil Mechanics , 1969 .

[18]  D. Fredlund,et al.  The shear strength of unsaturated soils , 1978 .

[19]  P. J. Grabe,et al.  Effects of Principal Stress Rotation on Permanent Deformation in Rail Track Foundations , 2009 .

[20]  Christian Madshus,et al.  HIGH-SPEED RAILWAY LINES ON SOFT GROUND: DYNAMIC BEHAVIOUR AT CRITICAL TRAIN SPEED , 2000 .

[21]  Jie Han,et al.  A full-scale physical model test apparatus for investigating the dynamic performance of the slab track system of a high-speed railway , 2016 .

[22]  Y. Cui,et al.  Yielding and plastic behaviour of an unsaturated compacted silt , 1996 .

[23]  A. Skempton.  THE PORE-PRESSURE COEFFICIENTS A AND B , 1954 .

[24]  Geert Lombaert,et al.  The control of ground-borne vibrations from railway traffic by means of continuous floating slabs , 2006 .

[25]  Victor V. Krylov,et al.  Generation of Ground Vibrations by Superfast Trains , 1995 .

[26]  Nils-Erik Wiberg,et al.  Coupled simulation of wave propagation and water flow in soil induced by high‐speed trains , 2008 .

[27]  Louise Otter.  The influence of suction changes on the stiffness of railway formation , 2011 .

[28]  Takahisa Nakamura,et al.  Roadbed Degradation Mechanism under Ballastless Track and Its Countermeasures , 2006 .

[29]  G. Gitirana.  Weather-related geo-hazard assessment model for railway embankment stability , 2005 .

[30]  Erol Tutumluer,et al.  Laboratory Characterization of Coal Dust Fouled Ballast Behavior , 2008 .

[31]  F. E. Richart,et al.  Closure of "Capillary Effects on Dynamic Modulus of Sands and Silts" , 1984 .

[32]  W. Powrie,et al.  Dynamic Stress Analysis of a Ballasted Railway Track Bed during Train Passage , 2009 .

[33]  Delwyn G. Fredlund,et al.  Shear Strength Criteria for Unsaturated Soils , 2011 .

[34]  C.R.I. Clayton,et al.  Deformation measurement on a heavy haul track formation. , 2005 .

[35]  S. Pudasaini,et al.  A two‐phase mechanical model for rock‐ice avalanches , 2014 .

[36]  Yunmin Chen,et al.  Track and ground vibrations generated by high-speed train running on ballastless railway with excitation of vertical track irregularities , 2015 .

[37]  Louay N. Mohammad,et al.  Permanent Deformation Characterization of Subgrade Soils from RLT Test , 1999 .