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A Study on the Consolidation Characteristics Using the Constant Strain Rate Test of Remolded Gwangyang Marine Clay

일정변형률 시험을 이용한 재성형 광양 해성점토의 압밀특성 연구

Joeng-Min Jang1
,
Jin-Young Kim1
,
Woon-Ki Joeng1
,
Jin Choi1
,
Young-Sik Jin1
,
Kwon-Soo Kang2
,
Won-Jin Baek3
,
Kang-Il Lee4*
장 정민1
,
김 진영1
,
정 운기1
,
최 진1
,
진 영식1
,
강 권수2
,
백 원진3
,
이 강일4*
1Graduate students, Department of Rural & Boisystems Eingineering, Chonnam National University
2Professor, Department of Civil Engineering, Seonam University
3Associate Professor, Department of Rural & Boisystems Eingineering, Chonnam National University
4Professor, Department of Civil Engineering, Dae-Jin University
*교신저자. *Corresponding Author. 
30 December 2014. pp. 33-43
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Abstract

Recently, the case to construct the structure on the soft clayey ground has increased and in order to the reduction of the cost of construction and maintenance on the social infrastructure facilities we have been trying to improve the soft clayey ground using the existing methods such as the pre-loading method and the vertical drain method. Like this, when various ground improvement methods are applied on the soft clayey ground, a long-term consolidation settlement will be key issue due to low permeability coefficient of cohesive soil. According to existing research results that relate to the consolidation settlement, the loading periods for existing the standard consolidation test (Oedometer test) to obtain the consolidation parameters are needed for minimum ten days or more. Therefore, in this study, the standard consolidation test (24 hours step-loading) and constant strain rate consolidation test changed by strain rate was performed using the remolded marine clay on Gwangyang bay composed of a soft clayey ground of the south-west coast. From the laboratory test results, the characteristics of compression, strain-effective stress relations by constant strain rate and the variation characteristic of the pore water pressure by different of loading speed and the relation between consolidation parameters and constant strain rate are compared and analyzed.

Keywords
Consolidation
Ground improvement
Constant strain rate
Loading periods

최근 들어 연약지반상에 구조물을 건설하는 경우가 증가하고 있으며, 사회기반 시설의 유지관리 및 건설 비용의 절감을 위해 사전압밀공법 및 연직배수공법과 같은 기존의 방법을 이용하여 지반 개량이 행해지고 있다. 이와 같이 연약점성토 지반상에 다양한 개량공법이 적용 될 때, 점성토의 낮은 투수계수로 인한 장기간에 걸친 압밀침하가 중요하게 된다. 압밀침하와 관련된 기존 연구결과에 따르면, 기존의 표준압밀시험의 재하기간은 압밀정수 산정에 최소한 10일 이상의 시간을 요하게 된다. 따라서 이 연구에서는 서남해안의 대표적인 연약지반으로 구성된 광양만 재성형 해성점토를 이용하여 표준압밀시험과, 일정변형률 압밀시험의 변형률 속도를 변화시킨 실험을 수행하였다. 실내시험결과를 통해 등변형률 속도에 따른 압축특성, 변형률-유효응력관계, 재하속도에 따른 간극수압 변화특성, 압밀정수와 등변형률 속도의 관계를 비교/분석하였다.

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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 : 13
  • No :4
  • Pages :33-43
  • Received Date : 2014-10-11
  • Revised Date : 2014-11-03
  • Accepted Date : 2014-11-04
  • DOI :https://doi.org/10.12814/jkgss.2014.13.4.033
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