Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
권호 표지
DOI QR코드

DOI QR Code

Density Effect on Suction Stress Characteristics of Compacted Weathered Gneiss Soils

편마풍화토의 다짐밀도에 따른 불포화 흡수응력 특성

  • Park, Seong-Wan (Dept. of Civil and Environmental Eng., Dankook Univ.) ;
  • Kim, Byeong-Su (Dept. of Environmental and Civil Eng., Okayama Univ.) ;
  • Kwon, Hong-Gi (Dept. of Civil and Environmental Eng., Dankook Univ.) ;
  • Lim, Jae-Seong (Dept. of Civil and Environmental Eng., Dankook Univ.)
  • 박성완 (단국대학교 토목환경공학과) ;
  • 김병수 (오카야마대학교 환경디자인공학과) ;
  • 권홍기 (단국대학교 토목환경공학과) ;
  • 임재성 (단국대학교 토목환경공학과)
  • Received : 2012.11.14
  • Accepted : 2013.07.22
  • Published : 2013.08.31
Download PDF
⟨ Previous Next ⟩

Abstract

In order to examine the unsaturated shear strength characteristics of compacted weathered gneiss soils, the constant water content compression (CWCC) test was carried out. Specimens were made by static compaction under two densities conditions. The shear behavior in accordance with an initial suction obtained by varying initial degrees of saturation was evaluated. The suction could be directly measured by the use of the ceramic disk and the pore-water pressure transducer. The results of the peak shear strength from the CWCC test were examined using the relationship with Mp line from triaxial test under the saturated state, that is, by means of the suction stress which was calculated using the measured suction. In addition, the applicability of the suctions stress to the unsaturated shear behaviour of compacted weathered gneiss soils was discussed by applying Suction stress-SWCC Method (SSM).

본 연구에서는 다짐된 편마풍화토의 불포화토 전단강도특성을 규명하기 위하여, Constant Water Content Compression (CWCC) 시험을 실시하였다. 두 가지 상대밀도로 구분하여 정적 다짐으로 공시체가 제작되었고, 초기 포화도를 변화시킴으로써 초기 흡수력 및 최대전단강도가 구현될 때의 흡수력에 따른 전단거동을 살펴보았다. 흡수력은 세라믹디스크와 간극수압계의 설치에 의해 직접 측정되었고, 이 흡수력을 적용하여 흡수응력(ps)이 추정되었다. CWCC 시험에서 얻어진 최대압축강도에 대한 결과는 삼축압축시험에서의 포화상태 파괴선(Mp Line)과의 관계, 즉 흡수력에 의해 발현된 전단강도의 변화를 흡수응력을 이용하여 살펴보았다. 또한, Kim 등(2010)이 제안한 Suction stress-SWCC Method (SSM)을 활용하여 흡수응력의 적용성에 대해 논하였다.

Keywords

References

  1. Baker, R. and Frydman, S. (2009), "Unsaturated soil mechanics: Critical review of physical foundations", Engineering Geology, Vol.106, pp.26-39. https://doi.org/10.1016/j.enggeo.2009.02.010
  2. Bishop, A.W. (1959), "The principle of effective stress", Tecnisk Ukeblad, 39: 859-863.
  3. Bishop, A. W. and Blight G. E. (1963), "Some aspects of effective stress in saturated and partially saturated Soils", Geotechnique, Vol.13, pp.177-197. https://doi.org/10.1680/geot.1963.13.3.177
  4. Bishop, A.W. and Donald, I.B. (1961), "The experimental study of partly saturated soil in the triaxial apparatus", Pro. 5th Int. Conf. on Soil Mech. and Foundation Eng., Paris, Vol.1, pp.13-21.
  5. Chae, J.G., Kim, B.S, Park, S.W., and Kato, S. (2010), "Effect of suction on unconfined compressive strength in partly saturated soils", KSCE Journal of Civil Engineering, Vol.14, No.3, pp.281-290. https://doi.org/10.1007/s12205-010-0281-7
  6. Cunningham, M.R., Ridley, A.M., Dineen, K., and Burland, J.B. (2003), "The mechanical behavior of a reconstituted unsaturated silty clay", Geotechnique, Vol.53, No.2, pp.183-194. https://doi.org/10.1680/geot.2003.53.2.183
  7. Fredlund, D. G. and Morgenstern, N. R. (1977), "Stress state variables for unsaturated soils", Journal of Geotechnical Engineering, ASCE, Vol.103, pp.447-466.
  8. Fredlund, D. G., Morgenstern, N. R., and Widger, R. A. (1978), "The shear strength of unsaturated soils", Canadian Geotechnical Journal, Vol.15, No.3, pp.313-321. https://doi.org/10.1139/t78-029
  9. Fredlund, D. G. and Rahardjo, H. (1993), Soil mechanics for unsaturated soils, John Wiley & sons, New York.
  10. Karube, D. and Kato, S. (1994), "An Ideal unsaturated soil and the Bishop's soil. Proceeding of 13th International Conference", Soil Mechanics and Foundation Engineering, New Delhi, Vol.1, pp.43-46.
  11. Karube, D., Kato, S., Hamada, K., and Honda, M. (1996), "The Relationship between the mechanical behavior and the state of pore-water in unsaturated soil", Journal of Geotechnical Engineering, JSCE, Vol.535, No.III-34. pp.83-92.
  12. Karube, D. and Kawai, K. (2001), "The role of pore water in the mechanical behavior of unsaturated soils", Geotech. Geological Eng., Vol.19, pp.211-241. https://doi.org/10.1023/A:1013188200053
  13. Kato, S., Yoshimura, Y., Kawai, K., and Sunden, W. (2001), "Effects of suction on strength characteristics of unconfined compression test for a compacted silty clay", Geotechnical Engineering Journal, JSCE, Vol.687, pp.213-218.
  14. Kohgo, Y., Nakano, M., and Miyazaki, T. (1993), "Theoretical aspects of constitutive modeling for unsaturated soils", Soils and Foundations, Vol.33, No.4, pp.49-63. https://doi.org/10.3208/sandf1972.33.4_49
  15. Kim, B.S., Shibuya, S., Park, S.W., and Kato, S. (2010), "Application of suction stress for estimating unsaturated shear strength of soils using direct shear testing under low confining pressure", Canadian Geotechnical Journal, Vol.47, No.9, pp.955-970. https://doi.org/10.1139/T10-007
  16. Kohgo, Y., Nakano, M., and Miyazaki, T. (1993), "Theoretical aspects of constitutive modeling for unsaturated soils", Soils and Foundations, Vol.33, No.4, pp. 49-63. https://doi.org/10.3208/sandf1972.33.4_49
  17. Kwon, H.G. and Park, S.W. (2011), "Suction stress and unconfined compressive strength of compacted unsaturated silty sands", Journal of the Korean Geotechnical Society, Vol.27, No.8, pp.31-37. (In Korean) https://doi.org/10.7843/kgs.2011.27.8.031
  18. Lu, N. and Likos, W. L. (2006), "Suction stress characteristics curve for unsaturated soil", Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol.132, No.2, pp.131-142. https://doi.org/10.1061/(ASCE)1090-0241(2006)132:2(131)
  19. Maatouk, A., Lerouleil, S., and Rochelle, P.L.A. (1995), "Yielding and critical state of a collapsible unsaturated silty soil", Geotechnique, Vol.45, No.3, pp.465-477. https://doi.org/10.1680/geot.1995.45.3.465
  20. Nishimura, T. and Fredlund, D. G. (2000), "Unconfined compressive strength of a silty soil and kaolin below the residual state", Advances in Unsaturated Geotechnics, GSP No.99, ASCE, pp. 262-274.
  21. Ridley, A.M. (1995), "Strength-suction-moisture content relationships for kaolin under normal atmospheric conditions", Unsaturated soils, Balkema, Vol.1, pp.645-651.
  22. Satija, B.S. and Gulhati, S.K. (1979), "Strain rate for shear testing of unsaturated soil", Pro. 6th Asian Regional Conf. on Soil Mech. and Foundation Eng., Singapore, pp.83-86.
  23. Sheng, D., Zhou, A., and Fredlund, D. G. (2011), "Shear strength criteria for unsaturated soils", Geotechnical and Geological Engineering, Vol.29, No.2, pp.145-159. https://doi.org/10.1007/s10706-009-9276-x
  24. Shimizu, S. and Tabuchi, T. (1993), "Effective stress behavior of clays in unconfined compression tests", Soils and foundations, Vol.33, No.3, pp.28-39. https://doi.org/10.3208/sandf1972.33.3_28
  25. Toll, D.G. (1990), "A frame work for unsaturated soil behavior", Geotechnique, Vol.40, No.1, pp.31-44. https://doi.org/10.1680/geot.1990.40.1.31
  26. Vanapalli, S. K., Fredlund, D. G., Pufahl, D. E., and Clifton, A. W. (1996), "Model for the prediction of shear strength with respect to soil suction", Canadian Geotechnical Journal, Vol.33, pp.379-392. https://doi.org/10.1139/t96-060
  27. Wheeler, S.J. and Sivakumar, V. (1995), "An elasto-plastic critical state framework for un-saturated soil", Geotechnique, Vol.45, No.1, pp.35-53. https://doi.org/10.1680/geot.1995.45.1.35