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Local Uncertainty of the Depth to Weathered Soil at Incheon Songdo New City

인천송도신도시 풍화토층 출현심도의 국부적 불확실성

  • Kim, Dong-Hee (Infrastructure Engineering Team, SK E&C Co.) ;
  • Ko, Sung-Kwon (Vietnam Business Unit, Posco E&C Co.) ;
  • Lee, Woo-Jin (School of Civil, Environmental and Architectural Engrg., Korea Univ.)
  • 김동휘 (SK건설 Infra기술1팀) ;
  • 고성권 (포스코건설 베트남사업본부) ;
  • 이우진 (고려대학교 건축.사회환경공학부)
  • Received : 2011.09.30
  • Accepted : 2012.11.11
  • Published : 2012.11.28

Abstract

Since geologic data are often sampled at sparse locations, it is important not only to predict attribute values at unsampled locations, but also to assess the uncertainty attached to the prediction. In this paper, the assessment of the local uncertainty of prediction for the depth to weathered soil was performed by using the indicator kriging. A conditional cumulative distribution function (ccdf) was first modeled, and then E-type estimate was computed for the spatial distribution of the depth to the weathered soil. Also, optimal estimate of spatial distribution for the depth to weathered soil was determined by using ccdf and loss function. The design procedure and method considering the minimum expected loss presented in this paper can be used in the decision-making process for geotechnical engineering design.

일부 지점에서 수행된 시추조사결과를 이용하여 미조사구간의 지층분포를 추정하는 경우, 예측하고자 하는 변수들의 공간적인 분포 추정뿐만 아니라 추정결과에 수반되는 불확실성을 정량적으로 평가하는 것도 중요하다. 본 논문에서는 송도신도시 풍화토층 출현심도 추정결과의 국부적 불확실성을 지시자 방법을 이용하여 평가하였다. 지시자 방법을 이용하여 작성한 각 위치에서의 조건부 누적분포함수의 평균을 이용하여 송도신도시 풍화토층 출현심도의 공간적 분포를 추정하였다. 또한, 조건부 누적분포함수와 손실함수를 이용하여 송도신도시의 최적 풍화토층 출현심도를 결정하였다. 본 논문에서 이용한 손실함수를 고려할 수 있는 설계방법이 지반공학분야에도 잘 적용될 수 있음을 확인하였다.

Keywords

References

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