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http://dx.doi.org/10.7843/kgs.2022.38.12.113

Evaluation for the Manufacturing Characteristics and Thermal Conductivity of Engineering Scale Bentonite-Sand Buffer Blocks  

Lee, Deuk-Hwan (Disposal Safety Evaluation Research Division, KAERI)
Yoon, Seok (Disposal Safety Evaluation Research Division, KAERI)
Kim, Jin-Seop (Disposal Performance Demonstration Research Division, KAERI)
Lee, Gi-Jun (Disposal Safety Evaluation Research Division, KAERI)
Kim, Ji-Won (Disposal Performance Demonstration Research Division, KAERI)
Kim, Min-Jun (Deep Geologic Disposal&storage Research Center, KIGAM)
Publication Information
Journal of the Korean Geotechnical Society / v.38, no.12, 2022 , pp. 113-123 More about this Journal
Abstract
The required density relationship according to the press pressure of the floating die method and the homogeneity of the density distribution in the buffer block was evaluated to analyze the manufacturing characteristics of engineering scale bentonite-sand buffer blocks. In addition, the thermal conductivity was measured and compared with that of the pure bentonite buffer block to evaluate the level of thermal conductivity performance improvement of the bentonite-sand buffer material. As a result, it was confirmed that the standard deviation of dry density decreased to 0.011 and showed a homogeneous density distribution under the condition of press pressure greater than 400 kg/cm2. Furthermore, as a result of the thermal conductivity test, the thermal conductivity of the buffer with optimum moisture content conditions was 1.345 and 1.261 W/(m·K) under the press pressure of 400 and 600 kg/cm2, respectively. It increased by 16.1% and 11.0% compared to the pure bentonite buffer material. Based on the results of this study, it is judged that it can be used as fundamental data for manufacturing a homogeneous bentonite-sand buffer block on an engineering scale.
Keywords
Bentonite-Sand; Buffer; Engineering-scale; Floating die press; High-level radioactive waste; Thermal conductivity;
Citations & Related Records
Times Cited By KSCI : 7  (Citation Analysis)
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