Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Assessment of Hydraulic Conductivity of Modified Bentonite and Local Soil Mixture under Salt Water Condition

개량 벤토나이트와 현장토 혼합 차수층의 염수조건하에서의 투수성 평가

  • Xu, Xin (Dept. of Civil and Environmental Engrg., Seoul National Univ.) ;
  • Oh, Myounghak (Coastal Disaster Prevention Research Center, Korea Institute of Ocean Science & Technology) ;
  • Park, Junboum (Dept. of Civil and Environmental Engrg., Seoul National Univ.)
  • 서흠 (서울대학교 건설환경공학부) ;
  • 오명학 (한국해양과학기술원 연안방재센터) ;
  • 박준범 (서울대학교 건설환경공학부)
  • Received : 2017.10.24
  • Accepted : 2017.11.14
  • Published : 2017.11.30
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Abstract

A bentonite mixing with local soil widely used as liner layer for landfill should have low permeability less than $1{\times}10^{-7}cm/s$. But there are several limitations of bentonite used as liner layer, such as drying shrinkage cracking, ineffective waterproof ability under salt water condition like flocculation under sea water. The purpose of this research is the development of a salt resistance bentonite by mixing sepiolite and guar gum to overcome the weak points of bentonite to get high water resistance capacity and permeability coefficient below $1{\times}10^{-7}cm/s$ under salt water condition. After having performed drying shrinkage cracking test, swelling index test, compaction test, and hydraulic conductivity test we confirmed the optimal mixing ratio of materials and evaluated the performance of materials.

벤토나이트와 현장토를 혼합하여 차수재료로 폐기물 매립장의 차수층에 많이 적용하고 있다. 차수층으로 사용되는 재료는 일반적으로 투수계수가 $1{\times}10^{-7}cm/s$ 이하인 재료를 사용한다. 벤토나이트를 현장에서 차수층 재료로 사용될 때 벤토나이트는 건조-수축 균열 발생 및 염수조건에서 팽창성 떨어지고 차수 기능을 상실하는 등의 문제점이 존재한다. 벤토나이트의 문제점을 극복하기 위해 본 연구에서는 균열 방지 및 해수조건에서 차수성을 확보할 수 있는 내염성 벤토나이트를 개발하였고, 건조수축균역 시험, 팽윤도 시험, 다짐시험 및 투수실험을 통해 내염성 벤토나이트의 혼합비 결정 및 성능을 평가하였다.

Keywords

References

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