Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Characteristics of 1D-Consolidation for Soft Clay Ground Based on a Elasto-Viscous Model

탄-점성 이론에 의한 점성토 지반의 1차원 압밀특성

  • 백원진 (전남대학교 지역.바이오시스템공학과) ;
  • 하성호 ((주) 서정엔지니어링) ;
  • 이강일 (대진대학교 건설시스템공학과) ;
  • 김진영 (전남대학교 지역.바이오시스템공학과) ;
  • 김주현 (일본 야마구치대학교 사회건설공학과)
  • Received : 2010.05.20
  • Accepted : 2010.07.23
  • Published : 2010.08.31
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Abstract

In this study, in order to investigate the characteristics of secondary consolidation in the soft clay ground, oedometer tests were carried out in a normally consolidated condition, and the consolidation characteristics of the soft clay ground were examined by the Finite Difference Method (FDM) based on the Elasto-Viscous model proposed by Yoshikuni. The consolidation tests adjusted the consolidation load increment ratio(${\Delta}p/p_0$) to 1.0 for the four cases with initial consolidation pressures of 0.8, 1.6, 3.2, and 6.4 kgf/$cm^2$. The long-term consolidation tests were examined by the tests that changed the load increment ratio to clarify the effect of consolidation load increment. Although the numerical analysis was delayed in the primary consolidation process, from the result of the numerical analysis of the laboratory tests, the applicability of the Elasto-Viscous model was verified from the agreement of the secondary consolidation process. Based on the developing of model ground consist of general soft clay, influences of consoliation parameters on the consolidation characteristics were studied by the numerical analysis.

본 연구에서는 점성토지반에서의 이차압밀특성을 규명하기 위해 정규압밀 영역에 대해 표준압밀시험을 수행하고, Yoshikuni가 제안한 탄-점성 압밀이론의 유한차분해석결과를 이용하여 점성토지반의 압밀특성을 조사하였다. 압밀시험은 초기압밀하중 0.8, 1.6, 3.2, 6.4kgf/$cm^2$의 4케이스에 대해 압밀하중 증분비(${\Delta}p/p_0$)를 1.0으로 하여 수행하였다. 또한 압밀하중증분비의 영향을 명확히 하기 위해 압밀하중 증분비를 변화시킨 장기압밀시험을 수행하였다. 얻어진 실내실험결과에 대해 탄-점성 압밀이론을 이용한 수치해석을 실시한 결과, 수치해석결과가 1차압밀과정에서 약간지연(또는 조기진행)되는 결과가 얻어졌지만, 이차압밀과정에 대해서는 잘 일치한 것으로부터 그 적용성을 검증하였다. 또한 일반적인 점성토지반의 모델지반을 작성하고 압밀특성에 영향을 미치는 압밀정수에 대해 수치모델링을 수행하고 그 영향에 대해서 분석하였다.

Keywords

References

  1. 백원진 (2007a), "탄-점성 압밀이론에 의한 버티칼 드레인 타설 지반의 잔류침하 예측(I)-이론의 적용성 검증-", 한국지반공학회 논문집, Vol.23, No.6, pp.85-95.
  2. 백원진, 이강일, 김우진 (2007b), "탄-점성 압밀이론에 의한 버티칼 드레인 타설지반의 잔류침하 예측(II)-현장조건에의 적용성-", 한국지반공학회 논문집, Vol.23, No.4, pp.69-77.
  3. Aboshi, H. and Matsuda, H. (1981), "Secondary compression of clays and its effect on settlement analysis", Soils and Foundations, Vol.29, pp.19-24 (in Japanese).
  4. Adachi, T. and Oka, F. (1982), "Constitutive equations for normally consolidated clay based on elsto-viscoplasticity", Soils and Foundations, Vol.22, No.4, pp.57-70. https://doi.org/10.3208/sandf1972.22.4_57
  5. Baek, W.J. and Moriwaki, T. (2006), "Numerical analyses on consolidation of clayey ground improved by vertical drain system based on 3-D Elasto-Viscous model", Soils and Foundations, Vol.46, No.2, pp.159-171. https://doi.org/10.3208/sandf.46.159
  6. Bjerrum, L. (1967), "Engineering geology of Norwegian normallyconsolidated marine clays as related to settlements of buildings", Geotechnique, Vol.17, pp.81-118.
  7. Imai, G. (1989), "A unified theory of one-dimensional consolidation with creep", Proc. Of the 12th I.C.S.M.F.E., Vol.1, pp.57-60.
  8. Imai, G., Tanaka, Y. and Saegusa, H. (2003), "One-dimensional consolidation modeling based on the isotache law for normally consolidated clays", Soils and Foundations, Vol.43, No.4, pp.173-188. https://doi.org/10.3208/sandf.43.4_173
  9. Kutter, B. L. and Sathialingam, N. (1992), "Elastic-visco plastic modeling of the rate-dependent behaviour of clays", Geotechnique, Vol.42, No.3, pp.427-441. https://doi.org/10.1680/geot.1992.42.3.427
  10. Ladd, C. C., Foott, R., Ishihara, K., Schosser, F. and Poulos, H. J. (1977), "Stress -deformation and strength characteristics", Proc. 9th ICSMFE, Tokyo 2. State of the art report, pp.421-494
  11. Mesri, G., Bhahien, M. and Feng, T. W. (1995), "Compresssibility parameters during primary consolidation", Compression and Consolidation of clayey soils, Yoshikuni, H. and Kusakabe, O. (eds), Balkema, Rotterdam, pp.815-832.
  12. Sekiguchi, H. and Torihara, M. (1976), "Theory of one-dimensional consolidation of clays with consideration of their rheological properties", Soils and Foundations, Vol.16, No.1, pp.27-44. https://doi.org/10.3208/sandf1972.16.27
  13. Tan, T. K. (1957), "Secondary Time Effects and Consolidation of Clays", Academia Sinica, Harbin, China
  14. Taylor, D. W. and Merchant, W. (1940), "A Theory of Clay Consolidation Accounting for Secondary Compression", Journ. Math. and Phys., Vol.19, No.3, pp.167. https://doi.org/10.1002/sapm1940191167
  15. Yin, J. H. and Graham, J. (1994), "Equibalent times and onedimensional elastic visto-plastic modeling of time-dependent stressstrain behavior of clays", Canadian Geotechnique Journal, Vol.31, pp.42-52. https://doi.org/10.1139/t94-005
  16. Yoshikuni, H. Kusakabe, O., Hirao, T. and Ikegami, S. (1994), "Elasto-viscous modeling of time dependent behaviour of clay", Proc. of the 13th ICSMFE, New Delhi, Vol.1, pp.417-420.
  17. Yoshikuni, H., Moriwaki, T., Ikegami, S. and Nishiumi, H. (1995), "Rebound due to partial unloading and subsequent recompression behavior in 1-D consolidation", Proc. of the International Symposium on Compression and Consolidation of Clayey Soils, IS-Hiroshima'95, Vol.1, pp.233-238.