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Evaluation of OCR Prediction Methods utilizing PCPT Data

피조콘시험결과를 활용한 OCR결정법의 평가

  • Kim, Dae-Kyu (Dept. of Civil Engineering, Sangmyung University)
  • 김대규 (상명대학교 건설시스템공학과)
  • Received : 2010.02.08
  • Accepted : 2010.04.09
  • Published : 2010.04.30

Abstract

The purpose of this study is to evaluate the capability of representative existing methods through which OCR of clayey soils can be predicted utilizing PCPT data. The existing methods include Schmertmann method, Chen and Mayne method using pore water pressures measured immediately behind the cone base $u_2$, Lunne et al. method, and the latest Abu-Farsakh method. The lab. and in-situ test results, conducted in Incheon port area, were used for the study. The predicted OCR values from the methods were compared with the reference values estimated from laboratory oedometer test. Lunne et al.(k=0.5) method provided relatively better result while all the prediction methods underestimated OCR.

본 연구에서는 피조콘시험결과를 활용하여 점성토의 과압밀비를 결정하는 대표적 방법들을 비교 평가하였다. 비교 대상으로, 가장 대표적 방법인 Schmertmann 법, Chen and Mayne 법(콘베이스에서 측정하는 $u_2$ 법), Lunne 등 법 및 가장 최근에 발표된 Abu-Farsakh 법을 선정하였다. 각 방법의 비교연구를 위하여 인천항 지역에서 수행된 실내 및 현장시험 결과를 활용하였다. 고려된 모든 방법은 과압밀비를 과소평가하였으며, 그 중 Lunne et al. 법이 k=0.5 경우에 있어 가장 양호를 결과를 보여주었다.

Keywords

References

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