Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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The proposal on the new method for accurate to measure the plastic limits

정확한 소성한계 측정을 위한 새로운 실험법 제안

  • Ko, Jae-Min (Division of Civil engineering, Chonbuk University) ;
  • Lee, Byung-Suk (Division of Civil engineering, Chonbuk University)
  • 고재민 (전북대학교 토목공학과) ;
  • 이병석 (전북대학교 토목공학과)
  • Received : 2018.03.12
  • Accepted : 2018.06.01
  • Published : 2018.06.30
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Abstract

An examination of the characteristics of the ground material in is very important in a ground investigation. Casagrande classified soil using the material properties of soils. The liquid-plastic limit test is useful for obtaining basic information of soil, and is an effective method for classifying silt and clay, as well as the material properties, such as shear strength, shrinkage, and expansion. Unlike the liquid limit test, the plasticity limit test is due to the ambiguity of the test procedure. Many geotechnical engineers and scholars have questioned the test results. In this study, a new plasticity limit method was used to compare with the thread rolling method with kaolinite, ilite and bentonite at a certain ratio, and samples were collected from the west coast of Korea. As a result of the comparison, the test value of the new test method showed high reproducibility because the error range of the test value of the conventional thread rolling test was only 10% but the error range of the new test values decreased to 2%. The difference in the slope of the existing plasticity test values was 0.1519 ~ 0.1925, and the results of the test were similar or coincided with each other. Aone - point method was proposed to make it easier to apply the new test method.

지반조사에서 지반재료 특성의 판단은 매우 중요하다. Casagrande는 재료적 특성을 이용하여 흙을 분류하였다. 액 소성한계 시험은 흙의 기본적인 정보를 얻기 유용하며 실트와 점토를 분류하는 효과적인 방법과 재료 특성인 전단강도, 수축, 팽창 등의 정보를 제공한다. 액성한계와 다르게 소성한계는 시험절차의 모호성으로 많은 지반 공학자 및 기술자들이 시험결과에 의문을 제기하고 있다. 이를 해결하기 위해 낙하에너지를 이용한 새로운 소성한계 측정법을 제안하였다. 본 연구에서는 새로운 소성한계측정법의 정확성을 검토하기 위하여 새로운 카올리나이트, 일라이트, 벤토나이트를 각각 일정비율로 혼합하고 국내 서해안 일대의 시료를 채취하여 소성한계 측정법을 종래 방법과 비교 하였다. 비교 실험을 통한 검토결과 새로운 시험법의 시험값은 기존의 thread rolling시험의 시험값의 오차 범위가 10%에서 약 2%의 차이로 시험의 재현성이 높으며 기존 소성한계 시험값의 기울기와 차이가 0.11519 ~ 0.1925로 거의 시험의 결과 값이 유사 또는 일치하고 있음을 알 수 있었다. 또한 새로운 시험법을 보다 간편하게 적용할 수 있도록 일점법을 제안하였다.

Keywords

References

  1. Houlsby, G. T., "Theoretical analysis of the fall-cone test", Can. Geotech. J., vol. 32, no. 2, pp. 111-118, 1982. DOI: https://doi.org/10.1680/geot.1982.32.2.111
  2. Wood, D. M. Wroth, C. P., "The use of the cone penetrometer to determine the plastic limit of soils," Ground Eng., vol. 11, no. 3, pp. 37, 1978.
  3. Sherwood, P. T., "The reproducibility of the results of soil classification and compaction teests," TRRL Report LR339. Crowthorne, UK: Transport and Roda Research Laboratory, 1970.
  4. Feng, T. W., "Fall-cone penetration and water content relationship of clays", Geotechnique, vol. 50, no. 2, pp. 181-187, 2000. DOI: https://doi.org/10.1680/geot.2000.50.2.181
  5. Feng, T. W., "A linear log d-log w model for the determination of consistency limits of soils", Can. Geotech. J., 38, pp. 1335-1342, 2001. DOI: https://doi.org/10.1139/cgj-38-6-1335
  6. Feng, T. W., "Determining the consistency limits of high plasiticity clays by the BS fall cone method," gound engineering, 2004.
  7. Hansbo, S., "A new approach to the determination of the shear strength of clay by the fall-cone test", Royal Swedish Geotechnical. Institute Proc., Royal Swedish Geotechnical Institute, Stockholm, 14, pp. 7-47, 1957.
  8. Medhat, F & Whyte, I. L., "An appraisal of soil index tests," Engeng Geol, Special Publication 2, pp. 317-323, 1986. DOI: https://doi.org/10.1144/GSL.1986.002.01.55
  9. Sivakumar, V. Et al., "A new method of measuring plastic limit of fine materials," Geotechnique 59, no. 10, pp. 813-823, 2009. DOI: https://doi.org/10.1680/geot.2009.59.10.813
  10. Stone, K. J. L., Phan, K. D., "Cone penetration tests near the plastic limit," Geotechnique, vol. 45, no. 1, pp. 155-158, 1952. DOI: https://doi.org/10.1680/geot.1995.45.1.155
  11. Harison, J. A., "Using the BS cone penetrometer for the determination of the plastic limits of soils", Geotechnique, vol. 38, no. 3, pp. 433-438, 1988. DOI: https://doi.org/10.1680/geot.1988.38.3.433
  12. Skempton, A. W, Northey, R. D., "The sensitivity of clays," Geotechnique 3, No. 1, 30-53, 1952. DOI: https://doi.org/10.1680/geot.1952.3.1.30
  13. Wood, D. M., "19oil behaviour and critical state soil mechanics", 1st edn. Cambridge: Cambridge University Press.
  14. Tefra, T. H., "Measurement of plastic limit of cohesive soils," Statens vegvesen Nr. 208, 2013.
  15. Saxena. M., "An Energy Based Approach to Determine the Plastic Limit of Fine-Grained Soil using Modified Cone penetrometer," Procedia Technology, 25, pp. 162-169, 2016. DOI: https://doi.org/10.1016/j.protcy.2016.08.093
  16. Feng, T. W., "Using a Small Ring and a Fall-cone to Determine the Plastic limit", J. Geotech. Geoenviron. Eng., 2004, vol. 130, no. 6, pp. 630-635, 2004. https://doi.org/10.1061/(ASCE)1090-0241(2004)130:6(630)