The Journal of Engineering Geology (지질공학)

The Korean Society of Engineering Geology (대한지질공학회)
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Experimental Study on Ground Subsidence and Underground Cavity Expansion under Various Conditions

다양한 조건에 따른 지반함몰과 지중공동 확장에 대한 실험적 연구

  • Jeong, SeongYun (Department of Civil and Environmental Engineering, KAIST) ;
  • Karoui, Tarek (Department of Civil and Environmental Engineering, KAIST) ;
  • Jeong, YeongHoon (Department of Civil and Environmental Engineering, KAIST) ;
  • Kim, DongSoo (Department of Civil and Environmental Engineering, KAIST)
  • 정성윤 (한국과학기술원 건설및환경공학과) ;
  • 타렉 카루이 (한국과학기술원 건설및환경공학과) ;
  • 정영훈 (한국과학기술원 건설및환경공학과) ;
  • 김동수 (한국과학기술원 건설및환경공학과)
  • Received : 2017.05.10
  • Accepted : 2017.06.19
  • Published : 2017.06.30
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Abstract

Recently frequent occurrence of ground subsidence cases has become social issue, and people's concern on this problem has been growing accordingly. Meanwhile, understanding on the mechanism of ground subsidence formation is not enough. Therefore, this study aims for evaluating formation mechanism of ground subsidence under various groundwater conditions through model test when groundwater and soil are leaked together. Major factors found through model tests are direction of groundwater flow, head difference around the leakage point, and strehgth of the ground to support the underground cavity. Firstly, direction of groundwater flow has an influence on the direction of cavity expansion and ground collapse. Secondly, it is observed that the speed of ground subsidence formation increases as the head difference increases. Lastly, the expansion of the cavity can eventually lead to a sudden collapse.

최근 도심지에서 자주 발생하는 지반함몰 문제는 사회적 문제로 대두되고 있으며, 지반함몰에 대한 시민들의 우려는 증가하고 있다. 그에 비해 지반함몰 발생 메커니즘에 대한 이해는 부족한 실정이다. 따라서 본 연구에서는 모형실험을 통해 다양한 지하수 조건에서 지하수와 토사가 동시에 유실될 때의 지반함몰 발생 메커니즘을 평가하고자 한다. 실험을 통해서 밝혀진 지반함몰 메커니즘의 주요 인자는 지하수 흐름 방향, 유출부위 주변 수두차, 지중 공동 유지를 위한 지반 내 강도 등이다. 첫째로 지하수와 토사가 동시에 유실될 때 토사의 유실은 지하수 흐름 방향을 따라 발생하며 이는 지중 공동 생성 및 공동 확장 방향을 결정짓는 요소임을 확인했다. 둘째로 지하수 및 토사가 유실되는 위치 주변의 수두차가 높아질수록 지반함몰 발생 속도가 급격히 빨라지는 것이 실험적으로 확인되었다. 마지막으로 지중 공동 확장으로 인해 최종적으로 갑작스런 붕괴를 일으킬 수 있음이 확인되었다.

Keywords

References

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