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2019 Vol.35, Issue 8

Research Article

Proper Regulation of the Cutoff System in Offshore Landfill Built on Clay Ground with Double Walls

점토지반에 이중벽체가 적용된 해상폐기물매립장의 적정 차수 기준

Woong-Ki Hwang1
,
Hyang-Eun Kim2
,
Hoseong Choi3
,
Tae-Hyung Kim4*
황 웅기1
,
김 향은2
,
최 호성3
,
김 태형4*
1Member, Director, Geo R&D Co., Ltd.
2Member, Director, Geo R&D Co., Ltd.
3Dept. of Civil and Environmental Engrg., Korea Maritime and Ocean Univ.
4Member, Prof., Dept. of Civil Engrg., Korea Maritime and Ocean Univ.
1정회원, (주)지오알앤디 부장
2정회원, (주)지오알앤디 이사
3비회원, 한국해양대학교 토목환경공학과 석사졸업
4회원, 한국해양대학교 건설공학과 교수
* Corresponding Author
31 August 2019. pp. 5-15
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Abstract

이 연구는 오염원 유출을 방지하기 위한 해상폐기물매립장 차수시스템에 요구되는 적절한 기준을 제안하기 위해 수행되었다. 차수시스템은 바닥층과 연직벽으로 구성된다. 바닥층은 불투수 점토층으로 연직벽은 이중벽체로 외곽벽체는 강관쉬트파일로 외력에 대한 저항을 담당하고 연직내부벽체가 차수를 담당하는 것으로 가정하였다. SEEP/W와 CTRAN/W 프로그램을 이용하여 침투-이류-분산 해석을 정상류 및 비정상류 조건에서 실시하였다. 해석결과, 정상류 조건에서 비정상류 조건 보다 오염원 이동이 크게 나타나 설계관점에서 차수기준은 정상류조건에서 산정된 값을 적용하는 것이 타당한 것으로 나타났다. 바닥층의 점토지반이 균질하고 연직차수시스템의 시공에 문제가 없다는 전제하에 정상류조건에서 오염원 이동의 차수에 요구되는 점토층 및 연직차수벽의 투수계수, 두께, 근입깊이 등이 제안되었다.

This study was conducted to propose a reasonable requirement regulation of cutoff barriers composed of bottom layer and vertical barrier of offshore landfill for the prevention of contaminant leakage. The bottom layer was composed of impermeable clay layer; vertical walls were composed of double walls; outer wall was composed of steel sheet pile which registed against outer force; cutoff vertical barrier took the role of inner wall. Seepage-advection-dispersion numerical analysis was conducted using SEEP/W and CTRAN/W programs under steady and unsteady flows. The results showed that the values calculated under steady flow showed higher migration of pollutant than those of unsteady flow. The values calculated under steady flow are more valid from a design point of view. Under steady flow and the bottom clay layer and when the vertical barrier are homogeneous and completely well installed, respectively, the minimum required cutoff regulations for hydraulic conductivity, thickness, and embedded depth of the bottom clay layer and vertical barrier were suggested.

Keywords
Offshore landfill
Cutoff system
Bottom layer
Vertical Barrier
Steady and unsteady flows

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Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 35
  • No :8
  • Pages :5-15
  • Received Date : 2019-04-26
  • Revised Date : 2019-08-26
  • Accepted Date : 2019-08-26
  • DOI :https://doi.org/10.7843/kgs.2019.35.8.5
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