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Influence of Saturation and Soil Density on the Ground Subsidence Using Distinct Element Method

개별요소법을 통한 지반의 포화도와 밀도가 함몰에 미치는 영향 평가

  • Kim, Yeonho (Dept. of Civil & Environmental Eng., Dankook Univ.) ;
  • Kim, Hyunbin (Dept. of Civil & Environmental Eng., Dankook Univ.) ;
  • Park, Seong-Wan (Dept. of Civil & Environmental Eng., Dankook Univ.)
  • 김연호 (단국대학교 토목환경공학과) ;
  • 김현빈 (단국대학교 토목환경공학과) ;
  • 박성완 (단국대학교 토목환경공학과)
  • Received : 2018.04.18
  • Accepted : 2018.08.01
  • Published : 2018.08.31

Abstract

The collapse behavior of ground subsidence caused by continuous loss of particles depends on the saturated condition and density of the ground. In this study, types of ground subsidence were classified based on the saturated condition and each type was performed on the different relative density to analyze the influence factors on the collapse behavior by distinct element method. According to analysis results, the relatively small amount of settlement occurred on the dense ground and a cavity was created under dense-unsaturated ground. In contrast, loose ground showed the large amount of settlement and collapsed immediately without cavity formation even if the unsaturated ground was simulated. The results demonstrated that because the relative density has influence on the mechanical interlocking and saturated condition has influence on the inter-particle force, these are important factors to change the collapse behavior.

연속적인 입자 유실에 의해 발생하는 지반 함몰 유형은 지반의 포화상태 및 상대밀도에 따라 전개 거동이 다르게 발생한다. 본 연구에서는 지반의 포화상태에 따라 함몰 유형을 분류하고 각 유형에 대해 상대밀도에 따른 해석을 개별요소법을 통해 수행하여 영향 인자에 따른 지반 함몰 전개 거동 변화를 분석하였다. 조밀한 지반인 경우, 포화상태에서는 비교적 작은 침하량과 침하 영향범위가 발생하였고 부분포화상태에서는 지반 내부에 동공을 형성하는 결과를 보였다. 반면, 느슨한 지반인 경우, 포화상태에서는 침하량과 침하 영향범위가 크게 발생하였으며 부분포화상태에서도 동공을 형성하지 못하고 즉각적인 함몰이 발생하였다. 결과적으로 지반의 상대밀도 및 포화상태는 입자 사이에 작용하는 맞물림 효과에 큰 영향을 미치며 함몰 거동을 변화시키는 중요한 인자로 작용하는 것으로 나타났다.

Keywords

References

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