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2025 Vol.41, Issue 5 Preview Page
Effect of Bentonite Content and Temperature on Electrical Conductivity of Sodium Bentonite Slurries

벤토나이트 함량 및 온도에 따른 소듐 벤토나이트 슬러리의 전기전도도 특성에 관한 실험적 연구

Seolhee Han1
,
Sang Inn Woo2*
한 설희1
,
우 상인2*
1Member, Master Student, Dept. of Civil and Environmental Eng., Incheon National Univ.
2Member, Associate Prof., Dept. of Civil and Environmental Engineering, Incheon National Univ.
1정회원, 인천대학교 건설환경공학과 석사과정
2정회원, 인천대학교 건설환경공학전공 부교수
*Corresponding Author
31 October 2025. pp. 189-200
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Abstract

This study examined the correlation between the bentonite content and electrical conductivity of bentonite slurries and analyzed the effect of temperature variation on the evolution of the conductivity. The electrical conductivity increased with the bentonite content but exhibited a nonlinear trend, contrary to the linear previously reported relationship. The observed trend is attributed to the combined effect of ion release, which increases the conductivity, and decreased ion mobility at high ion concentrations, which suppresses the conductivity. The conductivity also increased with temperature but in a nonlinear pattern that cannot be explained simply by a reduction in the viscosity. The derived thermoelectric coefficient (α) revealed a nonlinear correlation, reflecting the complex effect of the bentonite content on the temperature sensitivity. This study demonstrates that conductivity-based evaluation provides a faster and more objective alternative to the methylene blue test and can be applied under high bentonite content and variable temperature conditions. Furthermore, it holds important implications for extending conductivity-based techniques to quality control and field applications of cut-off materials.

Keywords
Clay mineral
Electrical conductivity
Slurry
Sodium bentonite
Temperature

본 연구는 벤토나이트 슬러리의 벤토나이트 함량과 전기전도도의 상관성을 규명하고, 온도 변화가 전도도 거동에 미치는 영향을 분석하였다. 실험 결과, 벤토나이트 함량이 증가할수록 전기전도도는 상승했으나 기존의 선형 관계와 달리 비선형적 경향을 보였다. 이는 용출 이온 농도 증가가 전도도를 높이는 효과와, 높은 이온 농도에서 이동도가 저하되는 효과가 동시에 작용한 결과로 해석된다. 또한 온도 상승 시 전도도는 증가했지만 단순한 점성 감소로는 설명되지 않는 비선형적 거동을 나타냈다. 이를 정량화하기 위해 도출한 온도보정계수(α)는 비선형 상관성을 보여, 벤토나이트 함량이 전도도의 온도 민감도에 미치는 복합적 영향을 반영한다. 본 연구는 전기전도도를 활용한 벤토나이트 함량 평가 기법이 기존 메틸렌 블루 시험법보다 신속하고 객관적이며, 고함량 및 다양한 온도 조건에서도 적용 가능함을 시사한다. 이는 차수재 품질 관리와 현장 적용에서 전기전도도 기반 기법의 활용 가능성을 확장한다는 점에서 중요한 의의를 가진다.

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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 : 41
  • No :5
  • Pages :189-200
  • Received Date : 2025-09-29
  • Revised Date : 2025-10-10
  • Accepted Date : 2025-10-13
  • DOI :https://doi.org/10.7843/kgs.2025.41.5.189
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