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Research Article

Characteristics of Long-Term Settlement in the Soft Ground of Nakdong River by Numerical Analysis

수치해석에 의한 낙동강 하구 연약지반의 장기침하특성

Choon-Sik Park1
,
Mean-Young Ryu2*
박 춘식1
,
류 민영2*
1Member, Professor, School. of Civil, Environmental and Chemical Engineering, Changwon National Univ., 20 Changwondaehak-ro, Uichang-gu, Changwon-si, Gyeongsangnam-do 51140, Republic of Korea
2Member, Doctor of Engrg, Director, Sejin Engineering & Construction Co. Ltd., 6Fl, 304 Gamgye-ro, Buk-myeon, Uichang-gu, Changwon-si, Gyeongsangnam-do 51112, Republic of Korea
* Corresponding Author
30 September 2019. pp. 55-67
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Abstract

낙동강 하구 일대 대심도의 연약지반 지역은 시간 의존적인 2차압밀 특성 등의 원인으로 예측보다 실제 과다한 침하가 발생하므로 설계 시점부터 2차압밀 특성을 고려한 예측기법의 필요성이 요구된다. 따라서 본 연구에서는 2,000일 이상의 장기 계측자료 분석과 1차원 이론, 탄소성, 점･탄소성의 수치해석을 수행하여 장기침하 특성을 분석하였다. 그 결과 1차원 이론, 탄소성 해석 모두 성토 높이와 연약층 깊이에 따른 뚜렷한 상관관계를 찾을 수 없었으나, 점･탄소성 해석 방법은 장기계측 결과와 아주 유사하게 침하를 예측하였다. 따라서 연구 대상 지역과 같은 대심도 지역에서 장기 침하 예측 시 점･탄소성 해석을 시공 전에 적용하면 2차압밀 침하 거동 특성을 미리 예측하여 시공 중 발생할 수 있는 공기 지연과 경제적 손실을 사전에 방지할 수 있을 것으로 판단된다.

Deep soft ground in mouth of Nackdong river requires to be analysed with prediction method concerning characteristics of secondary consolidation from the beginning because it causes excessive settlement due to time-dependant secondary consolidation characteristics. This study investigated characteristics of extended settlement by conducting one-dimensional theory, elasto-plastic model and visco-elasto-plastic model as well as analyzing long-term measuring data observed over 2,000 days. According to one-dimensional theory and elasto-plastic model, there is not definite correlation between height of embankment and depth of soft ground while visco-elasto-plastic model showed similar result of settlement to that of long-term measuring data. Consequently it is suggested that applying visco-elasto-plastic model to developing deep underground place as studied area on predicting extended settlement before construction prevents economic loss and delay during process by preparing secondary consolidation characteristics.

Keywords
Deep Soft Ground
Consolidation
Long-Term Settlement
One-Dimensional Theory
Elasto-Plastic Model
Visco-Elasto-Plastic Model

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Information
  • Publisher :Korean Geosythetics Society
  • Publisher(Ko) :한국지반신소재학회
  • Journal Title :Journal of the Korean Geosynthetics Society
  • Journal Title(Ko) :한국지반신소재학회 논문집
  • Volume : 18
  • No :3
  • Pages :55-67
  • Received Date : 2019-08-07
  • Revised Date : 2019-09-19
  • Accepted Date : 2019-09-20
  • DOI :https://doi.org/10.12814/jkgss.2019.18.3.055
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