Nuclear Engineering and Technology

  • 제53권3호
  • /
  • Pages.1041-1048
  • /
  • 2021
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  • 1738-5733(pISSN)
  • /
  • 2234-358X(eISSN)
한국원자력학회 (Korean Nuclear Society)
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Measuring thermal conductivity and water suction for variably saturated bentonite

  • Yoon, Seok (Radioactive Waste Disposal Research Division, KAERI) ;
  • Kim, Geon-Young (Radioactive Waste Disposal Research Division, KAERI)
  • 투고 : 2020.01.30
  • 심사 : 2020.08.21
  • 발행 : 2021.03.25
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초록

An engineered barrier system (EBS) for the disposal of high-level radioactive waste (HLW) is composed of a disposal canister with spent fuel, a buffer material, a gap-filling material, and a backfill material. As the buffer is located in the empty space between the disposal canisters and the surrounding rock mass, it prevents the inflow of groundwater and retards the spill of radionuclides from the disposal canister. Due to the fact that the buffer gradually becomes saturated over a long time period, it is especially important to investigate its thermal-hydro-mechanical-chemical (THMC) properties considering variations of saturated condition. Therefore, this paper suggests a new method of measuring thermal conductivity and water suction for single compacted bentonite at various levels of saturation. This paper also highlights a convenient method of saturating compacted bentonite. The proposed method was verified with a previous method by comparing thermal conductivity and water suction with respect to water content. The relative error between the thermal conductivity and water suction values obtained through the proposed method and the previous method was determined as within 5% for compacted bentonite with a given water content.

키워드

과제정보

This research was supported by the Nuclear Research and Development Program (NRF-2017M2A8A5014857) and Basic Research Project (2020R1F1A1072379) of the National Research Foundation of Korea.

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