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http://dx.doi.org/10.7843/kgs.2019.35.11.7

Evaluation of Water Suction for the Compacted Bentonite Buffer Considering Temperature Variation  

Yoon, Seok (Radioactive Waste Disposal Research Division, KAERI)
Go, Gyu-Hyun (Dept. of Civil Engrg., Kumoh National Institute of Technology)
Lee, Jae-Owan (Radioactive Waste Disposal Research Division, KAERI)
Kim, Geon-Young (Radioactive Waste Disposal Research Division, KAERI)
Publication Information
Journal of the Korean Geotechnical Society / v.35, no.11, 2019 , pp. 7-14 More about this Journal
Abstract
The compacted bentonite buffer is one of the major components of an engineered barrier system (EBS) for the disposal of high-level radioactive waste (HLW), and it is considered the best candidate for the buffer material. The buffer is located between disposal canisters and near-field rock mass, and it interrupts the release of radionuclide from disposal canisters and protect them from the penetration of groundwater. At initial disposal condition, degree of saturation of the compacted bentonite buffer decreases because of high thermal quantities released from the disposal canisters. However, the degree of saturation of the compacted bentonite buffer gradually increases caused by inflow of groundwater. The saturated and unsaturated behavior of the buffer is a very important input data since it can determine the safety performance of EBS. Therefore, this paper investigated water retention capacity (WRC) for the Korean compacted bentonite buffer. The WRC of the compacted bentonite buffer was derived by measuring volumetric water content and water suction when temperature variation was between 24℃~125℃ considering decrease of degree of saturation with respect to temperature increase. The WRC was also derived with the same volumetric water content under the room temperature condition, and it showed 1~15% larger water suction than high temperature condition.
Keywords
Compacted bentonite buffer; Temperature variation; Water retention capacity; Water suction;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
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