Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Compressibility Characteristics Associated with Depositional Environment of Pusan Clay in the Nakdong River Estuary

낙동강 하구지역 부산점토의 퇴적환경에 따른 압축특성

  • Chung, Sung-Gyo (Dong-A Univ., School of Civil Engrg.) ;
  • Ninjgarav, E. (Mongolian Univ. of Science and Technology) ;
  • Ryu, Chun-Kil (Institute of Construction Technology and Urban Planning, Dong-A Univ.) ;
  • Jang, Woo-Young (Institute of Construction Technology and Urban Planning, Dong-A Univ.)
  • 정성교 (동아대학교 토목공학부) ;
  • ;
  • 류춘길 (동아대학교 건설기술연구소) ;
  • 장우영 (동아대학교 건설기술연구소)
  • Published : 2006.12.31
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Abstract

In the Nakdong River estuary soft and thick clay, which called Pusan clay, are deposited. Despite a number of great reclaimed projects that have been performed in the area, the consolidation settlement and time have been significantly underestimated due dominantly to sample disturbance, since the last decade. In order to resolve the underestmation, it was necessary to examine the compressibility characteristics through a systematic geotechnical investigation on the clay. In this study an advanced sampling technique was adopted on two sites chosen along the coastline, and then oedometer testing and geological investigation were performed for the undisturbed and reconstituted samples. As the results, the compressibility parameters of the clay were representatively determined, as well as their correlation. Particularly the effects of depositional environment on the physical indexes, level of structure, sample disturbance and compressibility parameters were analyzed for the clay.

낙동강 하구지역에는 부산점토라고 불리는 연약점토가 두텁게 분포하고 있다. 과거 10년 동안에 대단위 지반개량 사업이 수행되어 왔지만, 주로 시료교란 때문에 압밀침하량과 시간을 아주 과소평가하여 왔었다. 이를 극복하기 위하여 부산점토에 대한 체계적인 지반조사에 의하여 압축특성을 규명할 필요가 요구되었다. 따라서 본 연구에서는 해안지역의 두 현장에서 개선된 시료채취기술을 적용하여 얻어진 시료에 대하여 지질조사, 불교란 및 교란 시료에 대한 압밀실험이 수행되었다. 이 결과를 이용하여 각종 압축정수의 산정과 그들의 상관성을 규명하였으며, 특히 퇴적환경에 따라 물리적 특성, 구조수준, 교란도 및 압축정수의 변화를 분석하였다.

Keywords

References

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