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Identification of the Shear Velocities of Near Surface Soils Using Torsional Guided Waves

비틀림 유도파를 이용한 근지표면 전단속도 규명

  • 박경조 (전남대학교 기계자동차공학부) ;
  • 오형수 (전남대학교 기계자동차공학부)
  • Received : 2012.05.24
  • Accepted : 2012.07.05
  • Published : 2012.08.20

Abstract

A technique is presented that uses a circular waveguide for the measurement of the bulk shear(S-wave) velocities of unconsolidated, saturated media, with particular application to near surface soils. The technique requires the measurement of the attenuation characteristics of the fumdamental T(0,1) mode that propagates along an embedded pipe, from which the acoustic properties of the surrounding medium are inferred. From the dispersion curve analysis, the feasibility of using T(0,1) mode which is non-dispersive and have constant attenuation over all frequency range is discussed. The principles behind the technique are discussed and the results of an experimental laboratory validation are presented. The experimental data are best fitted for the different depths of wetted sand and the shear velocities as a function of depths are formulated using power law curves.

Keywords

References

  1. Lee, Y. S., 2010, Comparison of Window Functions for the Estimation of Leak Location for Underground Plastic Pipes, Transactions of the Korean Society for Noise and Vibration Engineering, Vol. 20, No. 67, pp. 568-576. https://doi.org/10.5050/KSNVE.2010.20.6.568
  2. Allene, D. N., Pavlakovic, B. and Cawley, P., 2001, Rapid, Long Range Inspection of Chemical Plant Pipework Using Guided Waves, Review of Progress in Quantitative Nondestructive Evaluation, Vol. 20A, pp. 180-187.
  3. Kwun, H., Kim, S. Y., Choi, M. S. and Walker, S., 2004, Torsional Guided Wave Attenuation in Coal-tar-enamel-coated Buried Piping, NDT&E International, Vol. 37, pp. 663-665. https://doi.org/10.1016/j.ndteint.2004.05.003
  4. Hua, J., Mu, J. and Rose, J., 2011, Guided Wave Propagation in Single and Double Layer Hollow Cylinders Embedded in Infinite Media, Journal of Acoustical Society of America, Vol. 129, pp. 691-700. https://doi.org/10.1121/1.3531807
  5. ASTM Standard D-4428/D-4428-94, 1994, Standard Test Methods for Cross-hole Seismic Testing, American Society for Testing Materials, pp. 885-898.
  6. Caradente, R., Ma, J. and Cawley, P., 2010, The Scattering of the Fundamental Torsional Mode from Axisymmetric Defects with Varying Depth Profile in Pipes, Journal of Acoustical Society of America, Vol. 127, pp. 3440-3448. https://doi.org/10.1121/1.3373406
  7. Cheng, J. W. and Yang, S. K., 2006, Torsional Guided Wave Attenuation in Buried Pipe, Materials Evaluation, Vol. 64, pp. 412-416.
  8. Long, R., Lowe, M. and Cawley, P., 2003, Attenuation Characteristics of the Fundamental Modes that Propagate in Buried Iron Water Pipes, Ultrasonics, Vol. 41, pp. 509-519. https://doi.org/10.1016/S0041-624X(03)00166-5
  9. Bachrach, R., Dvorkin, J. and Nur, A., 1998, High-resolution Shallow-seismic Experiments in Sand, Part II: Velocities in Shallow Unconsolidated Sand, Geophysics, Vol. 63, pp. 1234-1240. https://doi.org/10.1190/1.1444424
  10. Buckingham, M., 2000, Wave Propagation Stress Relaxation and Grain-to-grain Shearing in Saturated Unconsolidated Marine Sediments, Journal of Acoustical Society of America, Vol. 108, pp. 3561-3568.

Cited by

  1. Sludge Detection Inside Pipes Using Torsional Guided Waves vol.23, pp.3, 2013, https://doi.org/10.5050/KSNVE.2013.23.3.282