Development and Application of Penetration Type Field Shear Wave Apparatus

관입형 현장 전단파 측정장치의 개발 및 적용

  • Lee, Jong-Sub (Dept. of Civil and Environmental Engrg., Korea Univ.) ;
  • Lee, Chang-Ho (Dept. of Civil and Environmental Engrg., Korea Univ.) ;
  • Yoon, Hyung-Koo (Dept. of Civil and Environmental Engrg., Korea Univ.) ;
  • Lee, Woo-Jin (Dept. of Civil and Environmental Engrg., Korea Univ.) ;
  • Kim, Hyung-Sub (Busan New Port North Terminal Project, Samsung Corporation)
  • 이종섭 (고려대학교 사회환경시스템공학과) ;
  • 이창호 (고려대학교 사회환경시스템공학과) ;
  • 윤형구 (고려대학교 사회환경시스템공학과) ;
  • 이우진 (고려대학교 사회환경시스템공학과) ;
  • 김형섭 (삼성물산 건설부문, 부산신항 북컨 2단계 현장)
  • Published : 2006.12.31

Abstract

The reasonable assessment of the shear stiffness of a dredged soft ground and soft clay is difficult due to the soil disturbance. This study addresses the development and application of a new in-situ shear wave measuring apparatus (field velocity probe: FVP), which overcomes several of the limitations of conventional methods. Design concerns of this new apparatus include the disturbance of soils, cross-talking between transducers, electromagnetic coupling between cables, self acoustic insulation, the constant travel distance of S-wave, the rotation of the transducer, directly transmitted wave through a frame from transducer to transducer, and protection of the transducer and the cable. These concerns are effectively eliminated by continuous improvements through performing field and laboratory tests. The shear wave velocity of the FVP is simply calculated, without any inversion process, by using the travel distance and the first arrival time. The developed FVP Is tested in soil up to 30m in depth. The experimental results show that the FVP can produce every detailed shear wave velocity profiles in sand and clay layers. In addition, the shear wave velocity at the tested site correlates well with the cone tip resistance. This study suggests that the FVP may be an effective technique for measuring the shear wave velocity in the field to assess dynamic soil properties in soft ground.

References

  1. 이창호, 이종섭, 윤형구, 쯩홍꿍, 조태현 (2006), '응력 유도 및 고유이방성에 다른 전단파 속도 특성', 2006 한국지반공학회 논문집, 22(11) pp.47-54
  2. 한국지반공학회 (2006), '지반구조물의 내진설계', 지반공학 시리즈, 구미서관
  3. Luke, B. A. and Stokoe, K. H. II (1998), 'Application of SASW method underwater', J. Geotech. Geoenviron. Eng., ASCE, 124(6), pp.523-53I https://doi.org/10.1061/(ASCE)1090-0241(1998)124:6(523)
  4. Shirley, D. J. and Hampton, L. D. (1978), 'Shear wave mea- surements in laboratory sediments', J. Acoustical Society of America, 63(2), pp.607-613 https://doi.org/10.1121/1.381760
  5. Stokoe, K. H. II, Wright, S. G., Bay, J. A., and Rosset, J. M. (1994), 'Characterization of geotechnical sites by SASW method', in Geophysical characterization of sites, ISSMFE Technical committee #10 edited by R. D. Woods, Oxford Publishers, New Delhi
  6. 이종섭, 이창호 (2006), '벤더 엘리먼트시험의 원리와 고려사항', 한국지반공학회 논문집, 22(5), pp.47-57
  7. Ismail, M. A. and Rarnrnah, K. J. (2006), 'A new setup for measuring Go during laboratory compaction', Geotech. Test. J., 29(4), pp.280-288
  8. Zeng, X. and Grolewski, B. (2005), 'Measurement of Gmax and estimation of $K_o$ of saturated clay using bender elements in an oedometer', Geotech. Test. J., 28(3), pp.264-274
  9. Lee, J. S., Fernandez, A. L., and Santamarina, J. C. (2005), 'S-wave velocity tomography: small-scale laboratory application', Geotech. Test. J., 28(4), pp.336-344
  10. Yamashita, S. and Suzuki, T. (2001), 'Small strain stiffness on anisotropic consolidated state of sands by bender elements and cyclic loading tests', Proc. 15th International Conference of Soil Mechanics and Geotechnical Engineering, Istanbul, pp.325-328
  11. Kuwano, R. and Jardine R. J. (2002), 'On the applicability of cross-anisotropic elasticity to granular materials at very small strains', Geotechnique, 52(10), pp.727-749 https://doi.org/10.1680/geot.52.10.727.38848
  12. Pennington, D. S., Nash, D. F. T., and Lings, M. L. (1997), 'Anisotropy of Go shear stiffuess in Gault Clay', Geotechnique, 47(3), pp.391-398 https://doi.org/10.1680/geot.1997.47.3.391
  13. Louie, J. N. (2001), 'Faster, Better: Shear wave velocity to 100meters depth from refraction microtremor arrays', Bulletin of Seismoloical Society of America, 91(2), pp.347-364 https://doi.org/10.1785/0120000098
  14. Shirley, D. J. (1978), 'An improved shear wave transducer', J. Acoustical Society of America, 63(5), pp.1643-1645 https://doi.org/10.1121/1.381866
  15. Xia, J., Miller, R. D., and Park, C. B. (1999), 'Estimation of near-surface shear-wave velocity by inversion of Rayleigh waves', Geophysics, 64, pp.691-700 https://doi.org/10.1190/1.1444578
  16. Stokoe, K. H. II and Hoar, R. J. (1978), 'Variables Affecting In Situ Seismic Measurements', Proceedings of the Conference on Earthquake Engineering and Soil Dynamics, ASCE Geotechnical Engineering Division, Vol. II, pp.919-939
  17. Park, C. B., Miller, R. D., and Xia, J. (1999). 'Multichannel analysis of surface waves(MASW)', Geophysics, 64(3), pp. 800-808 https://doi.org/10.1190/1.1444590
  18. Nazarian, S. and Stokoe, K. H. II (1984), 'In situ shear wave velocities from spectral analysis of surface wave', Proc. 8th Conf On Earthquake Eng., San Francisco, pp.31-38
  19. Park, H. C. and Kim, D. S. (2001), 'Evaluation of the dispersive phase and group velocities using harmonic wavelet transform', NDT&E Inter. 34. pp.457-467 https://doi.org/10.1016/S0963-8695(00)00076-1