Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
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Experimental and Numerical Studies for Sedimentation and Consolidation Characteristics of Dredged Soil in Songdo Area, Incheon

인천 송도지역 준설토의 침강 및 압밀특성에 대한 실험 및 해석적 연구

  • Lee, Chung-Won (National Civil Defense and Disaster Management Training Institute, Ministry of Public Safety and Security) ;
  • Choi, Hangseok (School of Civil, Environmental and Architectural Engineering, Korea University)
  • Received : 2015.10.21
  • Accepted : 2015.12.07
  • Published : 2016.02.01
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Abstract

Accurate settlement estimation of dredged soft soil deposits is significantly important to prevent potential disasters during land reclamation. An application of the non-linear finite strain consolidation theory is inevitable in dealing with a very soft ground formation such as dredged fill. In this paper, a series of the sedimentation-consolidation test, self-weight consolidation test and CRS test were conducted to clarify sedimentation and consolidation characteristics of dredged fill in the Songdo area, Incheon. In addition, the settlement of dredged fill was numerically simulated using the PSDDF program. The dredged soil obtained from the Songdo area was classified as low-compressible silt (ML) based on USCS (Unified Soil Classification System), and the final bulking factors were estimated to be 1.56 and 1.17 by Yano's method and the numerical simulation, respectively. This difference is attributable to relatively high reclaimed height and large permeability of dredged soil in this region.

연약지반의 특성에 부합하는 이론을 이용하여 침하량을 합리적으로 예측하는 것은 건설방재적 관점에서도 대단히 중요하다. 특히, 준설매립지반과 같은 초연약지반의 압밀거동 모사를 위해서는 비선형 유한변형 압밀이론을 적용할 필요성이 있다. 본 연구에서는 인천 송도지역 준설토의 침강 및 압밀특성을 파악하기 위하여 침강압밀시험, 자중압밀시험 및 CRS 압밀시험을 수행하였으며, 그 결과를 PSDDF를 이용한 수치해석의 입력치로 사용하여 준설매립지반의 거동을 해석하였다. 본 지역의 준설토는 통일 분류법에 의해 저압축성 실트(ML)로 분류되었으며, Yano법 및 수치해석을 통하여 얻어진 최종 체적변화비는 각각 1.56, 1.17로 나타났다. 이러한 결과의 차이는 계면고가 상대적으로 높고 투수성이 큰 해당 구간 준설매립토의 토질 특성에 기인한 것으로 사료된다.

Keywords

References

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