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http://dx.doi.org/10.7843/kgs.2020.36.10.33

An Evaluation of Soil-Water Characteristic Curve Model for Compacted Bentonite Considering Temperature Variation  

Yoon, Seok (Radioactive Waste Disposal Research Division, KAERI)
Jeon, Jun-Seo (Building Safety Research Center & Seismic Safety Research Center, KICT)
Go, Gyu-Hyun (Dept. of Civil Engrg., Kumoh National Institute of Technology)
Kim, Geon-Young (Radioactive Waste Disposal Research Division, KAERI)
Publication Information
Journal of the Korean Geotechnical Society / v.36, no.10, 2020 , pp. 33-39 More about this Journal
Abstract
A geological repository has been considered as an option for the disposal of high-level radioactive waste (HLW). The HLW is disposed in a host rock at a depth of 500~1,000 meters below the ground surface based on the concept of engineered barrier system (EBS). The EBS is composed of a disposal canister, buffer material, backfill material, and gap-filling material. The compacted bentonite buffer is very important since it can restrain the release of radionuclide and protect the canister from the inflow of ground water. The saturation of the buffer decreases because high temperature in a disposal canister is released into the surrounding buffer material, but saturation of the buffer increases because of the inflow of ground water. The unsaturated properties of the buffer are critical input parameters for the entire safety assessment of the engineered barrier system. In Korea, Gyeongju bentonite can be considered as a candidate buffer material, but there are few test results of the unsaturated properties considering temperature variation. Therefore, this paper conducted experiment of soil-water characteristic curve for the Gyeongju compacted bentonite considering temperature variation under a constant water content condition. The relative error showed approximately 2% between test results and modified van-Genuchten model values.
Keywords
Compacted bentonite; Engineered barrier system; Modified van-Genuchten model; Soil-water characteristic curve; Temperature variation;
Citations & Related Records
Times Cited By KSCI : 6  (Citation Analysis)
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