포화된 카올리나이트를 이용한 열전도계수 예측모델의 신뢰성 검토

Assessment of the Models for Predicting the Thermal Conductivity of Saturated Kaolinite

  • 이장근 (한국건설기술연구원 지반연구실) ;
  • 김학승 (한국건설기술연구원 지반연구실) ;
  • 강재모 (한국건설기술연구원 지반연구실) ;
  • 김영석 (한국건설기술연구원 지반연구실) ;
  • 배규진 (한국건설기술연구원 지반연구실)
  • 발행 : 2012.03.01

초록

동토를 대상으로 건설되는 지반구조물과 방사능 폐기물 처리장의 점토벽체의 성능을 결정하기 위해서는 정확한 세립토의 열전도계수 산정이 중요하다. 그러나 세립토의 경우 시료 성형과정에서의 교란, 포화상태 유지, 그리고 측정 장치의 장기발열로 인해 함수비 구배 발생과 같은 기존 열전도계수 측정 장비의 문제점으로 인해 열전도계수 측정에 오차가 발생한다. 본 연구에서는 압밀장비를 개조하여 열전도계수 측정용 니들프로브를 삽입한 상태에서 압밀시험을 활용하여 하중조건과 건조밀도의 변화에 따른 열전도계수를 연속적으로 측정하였다. 또한 실내실험 결과를 토대로 흙입자 구성성분의 열전도계수를 고려한 예측 모델의 신뢰성을 분석하였다.

Estimating the thermal conductivity of clayey soils is important for enhancing the performance of geoengineering structures in cold regions and clay barriers for nuclear waste repositories, but specimen disturbance, saturation, and heat boundary conditions of the test apparatus hinder reliable measurements of the thermal conductivity of saturated clayey soils. This paper presents the results of an experimental study carried out using modified consolidation tests with the needle probe method to measure thermal conductivity. Experimental consolidation tests with saturated kaolinite were performed to investigate the effect of effective stress and dry density on thermal conductivity for saturated kaolinite. In addition, thermal conductivity of soil particles were thoroughly investigated and experimental results were used to evaluate the accuracy of the models to predict thermal conductivity.

키워드

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