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Evaluation of Water Suction for Compacted Bentonite Buffer Under Elevated Temperature Conditions

  • Received : 2022.04.13
  • Accepted : 2022.06.27
  • Published : 2022.06.30

Abstract

A compacted bentonite buffer is a major component of engineered barrier systems, which are designed for the disposal of high-level radioactive waste. In most countries, the target temperature required to maintain safe functioning is below 100℃. If the target temperature of the compacted bentonite buffer can be increased above 100℃, the disposal area can be dramatically reduced. To increase the target temperature of the buffer, it is necessary to investigate its properties at temperatures above 100℃. Although some studies have investigated thermal-hydraulic properties above 100℃, few have evaluated the water suction of compacted bentonite. This study addresses that knowledge gap by evaluating the water suction variation for compacted Korean bentonite in the 25-150℃ range, with initial saturations of 0 and 0.22 under constant saturation conditions. We found that water suction decreased by 5-20% for a temperature increase of 100-150℃.

Keywords

Acknowledgement

This research was supported by the Nuclear Research and Development Program of the National Research Foundation of Korea (2021M2E3A2041312 and 2021M2E3A2041351).

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