Abstract 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.

中文翻译：

---

测量可变饱和膨润土的热导率和吸水率

摘要 一种用于处置高放废物（HLW）的工程屏障系统（EBS），由装有乏燃料的处置罐、缓冲材料、填隙材料和回填材料组成。由于缓冲器位于处置罐和周围岩体之间的空隙中，它可以防止地下水流入并阻止放射性核素从处置罐中溢出。由于缓冲液在很长一段时间内逐渐饱和，因此考虑到饱和条件的变化，研究其热-水-机械-化学 (THMC) 特性尤为重要。因此，本文提出了一种测量不同饱和度下单个压实膨润土的热导率和吸水率的新方法。本文还重点介绍了一种使压实膨润土饱和的简便方法。通过比较热导率和吸水率与含水量的关系，用先前的方法验证了所提出的方法。对于具有给定含水量的压实膨润土，通过所提出的方法获得的热导率和吸水值之间的相对误差被确定为在5%以内。