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Mechanical Characteristics of Dredged and Reclaimed Ground with Low Plasticity from Western Coastal Site

서해안 저소성 준설매립 지반의 역학적 특성

  • Received : 2015.11.14
  • Accepted : 2015.12.01
  • Published : 2015.12.30

Abstract

When carrying out design for soft ground improvement before reclamation of dredged soil, it is very important to appropriately evaluate design parameters such as compression index and undrained strength in order to estimate optimum construction cost. In this study, consolidation and strength parameters were estimated by the samples obtained from the similar reclaimed land. Water content and compression index of dredged soil reclaimed by hydraulic fill method were quite decreased in comparison with those of in-situ conditions at Incheon site. Relationships between compression index(Cc) and water content (wn), and between undrained strength (su) and water content (wn) for dredged soil were obtained by field vane test and oedometer test, respectively. Applicability of Schmertmann correction method (compression index) for low plasticity silty soil was discussed according to comparison with designed and measured settlements.

실제 현장에서 준설매립공사를 수행하기 전의 설계 단계에서, 연약지반 개량설계를 수행할 때, 압축지수와 비배수 전단강도와 같은 설계정수를 합리적으로 평가하는 것은 최적공사비 산정측면에서 매우 중요한 사항이라고 할 수 있다. 본 연구에서는 유사 준설매립 현장에서 실시된 원위치 전단강도시험 및 불교란 시료 채취를 통해서 압밀 및 강도정수를 평가하였다. 이때, 배사관을 이용한 준설매립방법으로 투기된 준설매립층의 함수비 및 압축지수는 원지반 조건보다 오히려 감소하는 경향을 나타냈다. 압밀시험에 의해 준설매립지반의 압축지수와 함수비의 관계, 원위치 베인전단 시험으로 비배수 전단강도와 함수비의 관계를 각각 평가하였으며, 저소성 실트지반에 대한 Schmertmann의 압축지수 보정방법의 적용성을 판단하기 위해서 실제 침하량과 설계 예측침하량의 비교 분석을 실시하였다.

Keywords

References

  1. Kim Sangkwi, Yea Geuguwen, Kim, Kilsu, Kim, Honeyeon., (2011), Compression Characteristics among Western and Southern Coastal Marine Clays - Incheon.Mokpo.Gwangyang.Busan, Korean Geo-Environmental Society, Vol.12, No.6, pp. 43-51.
  2. Imai. G., (1980). Settling behavior of caly suspension, Soils and Foundations 20(2), pp.61-77. https://doi.org/10.3208/sandf1972.20.2_61
  3. Egashira, K, Iwataki, K., Sato, T., Katagiri, M., and Yoshifuku, T. (2002), Predition and assessment of reclamation by dreged and marine clay, Journal of JSCE, No.715, III-60, pp.147-164.
  4. Samsung C&T. (2008). Report on geotechnical investigation, Container Terminal development project at Incheon new port, pp.40-53.
  5. Samsung C&T. (2014). Report on geotechnical investigation after dredged and reclamation and settlement monitoring, Container Terminal development project at Incheon new port, pp.88-93.
  6. Schmertmann J. H. (1953). Estimating the true consolidation behavior of clay from laboratory test results, Proceedings ASCE 79, pp.1-26.
  7. Terzaghi K. (1967). Soil mechanics in engineering practice, 2nd ed, Wiley, pp.72-83.
  8. Yano. K., (1985). Properties of very soft ground reclaimed by dredged marine clay and their prediction, Journal of Japanese society civil engineers 365(4), 1-14.

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  3. 단계성토에 따른 연약지반의 전단강도 및 압밀거동 특성 vol.21, pp.7, 2020, https://doi.org/10.14481/jkges.2020.21.7.17