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2014 Vol.30, Issue 2 Preview Page
Effects of Various Loading Periods on the Consolidation Characteristics of Remolded Clay - With Special Reference to Gwangyang Marine Clayey Soil -

하중재하기간이 재성형 점토의 압밀특성에 미치는 영향 - 광양항 해성점토를 중심으로 -

Jae-Cheol Hong1
,
Jin-Young Kim1
,
Jae-Rok Shim2
,
Kwon-Soo Kang3
,
Ju-Hyun Kim4
,
Won-Jin Baek5*
홍 재철1
,
김 진영1
,
심 재록2
,
강 권수3
,
김 주현4
,
백 원진5*
1Graduate Student, Dept. of Rural & Bio-Systems Engrg., Chonnam National Univ.
2Graduate Student, Dept. of Rural & Bio-Systems Engrg., Chonnam National Univ.
3Assistant Prof., Dept. of Civil Engrg., Seonam Univ.
4Graduate Student, Graduate School of Science and Engrg., Yamaguchi Univ., Japan
5Associate Prof., Dept. of Rural & Bio-Systems Engrg., Chonnam National Univ.
1전남대학교 지역․바이오시스템공학과 박사과정
2전남대학교 지역․바이오시스템공학과 박사과정
3서남대학교 토목공학과 조교수
4일본, 야마구치대학교 대학원 이공학연구과, 박사과정
5전남대학교 지역･바이오시스템공학과 부교수
*교신저자. *Corresponding Author. 
28 February 2014. pp. 53-64
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Abstract

This study sets it’s face to define effects of the various loading periods in normal consolidation area on clay’s compression and long-term consolidation characteristics through a laboratory test using homogeneous remolded clay. Moreover, by carrying out a long-term consolidation test which diversifies initial consolidation applicable to effective overburden loading in the various loading period. This study intended to suggest the method predicting the final settlement on the basis of loading periods by comparing and analyzing compression curve’s characteristics according to loading weight of each stage and increase in loading period when carrying out the standard consolidation test. From the test results, the study shows that as of the soft clay’s compression characteristics on the basis of various loading periods, preconsolidation load has a tendency to be decreased slightly as the loading period is getting more and more longer at each step after initial consolidation load puts on the remolded clay which is caused by secondary consolidation’s increase in the latter part of each phase. And those effects have an weaker influence on compression index in normal consolidation area at the same time as secondary consolidation brought out quasi-overconsolidation and stabilization of clay’s structure, have an influence re-compression index is increased in overconsolidation area on the other hand.

Keywords
Creep
Overconsolidation
Initial consolidation loads
Loading periods

이 연구에서는, 균질한 재성형 점토를 이용한 실내시험을 통해 정규압밀 영역에서의 하중재하기간이 점성토의 압축 및 장기압밀 특성에 미치는 영향을 명확히 하고자 하였다. 또한 각 하중재하기간에 따른 현장에서의 유효상재하중에 해당하는 초기압밀하중을 변화시킨 장기압밀 시험을 수행하여 표준압밀시험시의 하중단계별 재하방법과 하중재하기간의 증가에 따른 압축곡선의 특성을 비교/분석하여 하중재하기간에 따라 최종침하량을 예측하는 방법을 제안하고자 하였다. 연구 결과 하중재하기간에 따른 점성토의 압축특성은 초기압밀하중을 가한 후 하중재하기간이 증가할수록 주어진 단계에서의 압밀후반부의 2차압밀의 증가로 선행압밀하중이 약간씩 감소하는 경향을 나타내었다. 그와 동시에 2차압밀이 유사과압밀 현상 및 점토골격의 안정화를 유발하여 정규압밀영역에서의 압축지수에 미치는 영향은 미미했으며 과압밀영역에서는 유사과압밀 현상으로 재압축지수의 증가를 유발하는 것으로 나타났다.

References
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2
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15
Received : October 21st, 2013
16
Revised  : January 6th, 2014
17
Accepted : February 3rd, 2014
Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 30
  • No :2
  • Pages :53-64
  • Received Date : 2013-10-21
  • Revised Date : 2014-01-06
  • Accepted Date : 2014-02-03
  • DOI :https://doi.org/10.7843/kgs.2014.30.2.53
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