Using a seismic survey to measure the shear modulus of clean and fouled ballast

In this paper a first time attempt has been made to measure the low strain shear modulus of clean and fouled ballast using a seismic survey of Multi-channel Analysis of Surface Wave (MASW). A model rail track was built with nine sub-sections, each having different fouling characteristics. MASW survey was performed in the top of each section of ballast and shear wave velocity was measured. The shear modulus of ballast fouled by pulverized rock, clayey sand and coal was calculated by using shear wave velocities and densities of each section and presented. The optimum and critical fouling points are defined considering the shear stiffness and drainage criteria for ballast fouled by clayey sand and coal. In both cases the shear stiffness increased to a maximum and then decreased as the percentage of fouling increased. The degree of fouling corresponding to the maximum shear wave velocity is defined as the optimum fouling point. After a particular degree of fouling the shear stiffness decreased less than clean ballast and the corresponding drainage condition become unacceptable. This point is defined as the critical fouling point. The results obtained from the model track were compared with the field data.

[1]  Evaluation of Low Strain Dynamic Properties using Geophysical Method: A Case Study , 2008 .

[2]  T. G. Sitharam,et al.  Seismic microzonation of Bangalore, India , 2008 .

[3]  T. G. Sitharam,et al.  Mapping of Average Shear Wave Velocity for Bangalore Region: A Case Study , 2008 .

[4]  Frank Feldman,et al.  Alternative Testing Method for the Measurement of Ballast Fouling : Percentage Void Contamination , 2002 .

[5]  Ram M. Narayanan,et al.  RAILROAD TRACK MODULUS ESTIMATION USING GROUND PENETRATING RADAR MEASUREMENTS , 2002 .

[6]  Jianghai Xia,et al.  Multichannel analysis of surface waves to map bedrock , 1999 .

[7]  P. Mayne,et al.  FIELD AND LABORATORY MEASUREMENTS OF DYNAMIC SHEAR MODULUS OF PIEDMONT RESIDUAL SOILS , 1999 .

[8]  M O Al-Hunaidi,et al.  DIFFICULTIES WITH PHASE SPECTRUM UNWRAPPING IN SPECTRAL ANALYSIS OF SURFACE WAVES NONDESTRUCTIVE TESTING OF PAVEMENTS , 1992 .

[9]  Jianghai Xia,et al.  The Selection of Field Acquisition Parameters for Dispersion Images from Multichannel Surface Wave Data , 2004 .

[10]  W R Hudson,et al.  USE OF SPECTRAL ANALYSIS OF SURFACE WAVES METHOD FOR DETERMINATION OF MODULI AND THICKNESSES OF PAVEMENT SYSTEMS. , 1983 .

[11]  Nenad Gucunski,et al.  Detection of Underground Obstacles by SASW Method—Numerical Aspects , 1997 .

[12]  T. G. Sitharam,et al.  Seismic Microzonation: Principles,Practices and Experiments , 2008 .

[13]  T. G. Sitharam,et al.  Spatial Variability of the Depth of Weathered and Engineering Bedrock using Multichannel Analysis of Surface Wave Method , 2009 .

[14]  T. G. Sitharam,et al.  Site Characterization and Site Response Studies Using Shear Wave Velocity , 2008 .

[15]  Jianghai Xia,et al.  Estimation of near‐surface shear‐wave velocity by inversion of Rayleigh waves , 1999 .

[16]  Richard D. Miller,et al.  Multichannel analysis of surface waves , 1999 .

[17]  R E Ahlf.  M/W COSTS: HOW THEY ARE AFFECTED BY CAR WEIGHTS AND THE TRACK STRUCTURE , 1975 .

[18]  Michael Forde,et al.  The application of time domain ground penetrating radar to evaluate railway track ballast , 1999 .

[19]  Ernest T. Selig,et al.  Track Geotechnology and Substructure Management , 1995 .

[20]  Ali Ismet Kanli,et al.  VS30 mapping and soil classification for seismic site effect evaluation in Dinar region, SW Turkey , 2006 .

[21]  Ernest T. Selig,et al.  Static and Cyclic Triaxial Testing of Ballast and Subballast , 2005 .

[22]  T. G. Sitharam,et al.  Site classification and estimation of surface level seismic hazard using geophysical data and probabilistic approach , 2009 .

[23]  Manicka Dhanasekar,et al.  The effect of coal dust fouling on the cyclic behaviour of railtrack ballast , 2004 .

[24]  T. G. Sitharam,et al.  Relationship between Low Strain Shear Modulus and Standard Penetration Test N Values , 2010 .

[25]  J. M. Roesset,et al.  Characterization of geotechical sites by SASW method , 1994 .

[26]  Bei Su.  EFFECTS OF RAILROAD TRACK STRUCTURAL COMPONENTS AND SUBGRADE ON DAMPING AND DISSIPATION OF TRAIN INDUCED VIBRATION , 2005 .

[27]  T. G. Sitharam,et al.  Seismic Microzonation of Bangalore , 2007 .

[28]  Kenji Satake,et al.  Introduction to “Tsunami Science Four Years After the 2004 Indian Ocean Tsunami, Part II: Observation and Data Analysis” , 2009 .

[29]  Jianghai Xia,et al.  Quantitative estimation of minimum offset for multichannel surface-wave survey with actively exciting source , 2006 .