DOI QR코드

DOI QR Code

Interpretation of Empirical Cone Factors for Determining Undrained Strength

비배수강도 결정을 위한 콘 지수 연구

  • Kim, Dae-Kyu (Dept. of Civil Engineering, Sangmyung University)
  • 김대규 (상명대학교 건설시스템공학과)
  • Published : 2009.11.30

Abstract

The results of PCPT(Pezocone Penetration Test) are widely used for the estimation of the undrained shear strength, for which the empirical cone factors($N_{kt}$, $N_{ke}$, $N_{{\Delta}u}$) need to be obtained at each site. In this study, the cone factors were estimated, for the soils at Bookmyun area in Changwon city, using the undrained shear strengths from the unconfined and UU triaxial compression tests. The parametric studies with plastic index and pore water pressure ratio were performed as well. $N_{kt}$, $N_{ke}$ and $N_{{\Delta}u}$ were estimated in the ranges of 8~40, 7~37, and 1~26 respectively. It was observed that there is a relationship between the cone factors, specially $N_{{\Delta}u}$, and the pore pressure ratio.

콘 관입시험 결과는 현장의 비배수전단강도 결정을 위하여 광범위하게 활용되고 있으며, 이를 위하여 지역별로 적절한 경험적 콘 지수($N_{kt}$, $N_{ke}$, $N_{{\Delta}u}$)의 결정이 필요하다. 본 연구에서는 창원 북면 지역 지반에 대하여 일축 압축시험 및 비압밀비배수 삼축압축시험 결과를 이용하여 콘 지수를 산정하였으며, 소성지수 및 간극수압비와의 관계를 고찰하였다. $N_{kt}$, $N_{ke}$, $N_{{\Delta}u}$은 각각 8~40, 7~37, 1~26으로 산정되었으며, 간극수압비와 비교적 큰 연관성이 있음이 고찰되었다.

Keywords

References

  1. S. F. Su, H. J. Liao, "Influence of Strength Anisotropy on Piezocone Resistance in Clay," J. of Geotechnical and Geoenvironmental Engineering, pp. 166-173, Vol. 128, No. 2, Feb., 2002. https://doi.org/10.1061/(ASCE)1090-0241(2002)128:2(166)
  2. H. S. Yu, J. K. Mitchell, "Analysis of Cone Resistance: Review of Methods," J. of Geotechnical and Geoenvironmental Engineering, pp. 140-149, Vol. 124, No. 2, Feb., 1998. https://doi.org/10.1061/(ASCE)1090-0241(1998)124:2(140)
  3. T. Lunne, P. K. Robertson, J. J. M. Powell, Cone Penetration Testing, Blackie Academic and Professional, 1997.
  4. Sungjin Hong, Moonjoo Lee, Taejoon Kim, Woojin Lee, "Estimation of Cone Factors using Pore Pressure Ratio for clays in Busan, J. of Korean Geotechnical Society, pp. 77-88, Vol 25, No. 1, Jan., 2009.
  5. Korean Geothechnical Society, Interpretation and Application of Ground Exploration Results, Kumiseokwan, 2005.
  6. A. S. Vesic, "Expansion of Cavities in Infinite Soil Mass," J. of Soil Mechanics and Foundation Engineering, pp. 265-290. Vol. 98, No. 8, 1972.
  7. R. Salgado, J. K. Mitchell, M. Jamiolkowski, "Cavity Expansion and Penetration Resistance in Sand," J. of Geotechnical and Geoenvironmental Engineering, pp. 344-354. Vol. 123, No. 4, 1997. https://doi.org/10.1061/(ASCE)1090-0241(1997)123:4(344)
  8. M. M. Baligh, "Strain Path Method," J. of Soil Mechanics and Foundation Engineering, pp. 1108-1136 Vol. 111, No. 9, 1985.
  9. C. I. Teh, G. T. Houlsby, "An Analytical Study of the Cone Penetration Test in Clay," Geotechnique, London, UK, pp. 17-34, Vol. 41, No. 1, 1991. https://doi.org/10.1680/geot.1991.41.1.17
  10. V. van den Berg, Analysis of Soil Penetration, Ph.D. Thesis, Delft University, Delft, The Netherlands, 1994.
  11. J. H. Schmertmann, "Guidelines for Cone Penetration Test," Performance and Design, Federal Highway Administration, Report FHWA-TS-78-209, Washington, July, 1978.
  12. T. Lunne, H. P. Chrisoffersen, T. I. Tjelta, "Engineering Use of Piezocone Data in North Sea Clays," Pro. 11th Int. Conf. on Soil Mechanics and Foundation Engineering, Sanfrancisco, pp. 907-912, Vol. 2, 1985.
  13. R. G. Campanella, D. G. Gillespie, P. K. Robertson, "Pore Pressure during Cone Penetration Testing," Pro. 2nd European Syposium on Peneration Testing, Amsterdam, pp. 507-512, Vol. 2, 1982.
  14. R. G. Campanella, P. K. Robertson, D. G. Gillespie, J. Greig, "Recent Developements in insitu Testing of Soils," Pro. 11th Int. Conf. on Soil Mechanics and Foundation Engineering, Sanfrancisco, pp. 849-854, Vol. 2, 1985.

Cited by

  1. A Study on Cone Factors for Northeastern Part of Shiwha Area I : Evaluation and Pore Pressure Parameter vol.13, pp.1, 2012, https://doi.org/10.5762/KAIS.2012.13.1.406