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http://dx.doi.org/10.7843/kgs.2021.37.10.5

Evaluation of Mechanical Properties for the Compacted Bentonite Buffer Materials  

Yoon, Seok (Disposal Safety Evaluation Research Division, KAERI)
Hong, Chang-Ho (Disposal Performance Demonstration Research Division, KAERI)
Kim, Taehyun (Disposal Performance Demonstration Research Division, KAERI)
Kim, Jin-Seop (Disposal Performance Demonstration Research Division, KAERI)
Publication Information
Journal of the Korean Geotechnical Society / v.37, no.10, 2021 , pp. 5-11 More about this Journal
Abstract
The compacted bentonite buffer is one of the most important components in an engineered barrier system (EBS) to dispose of high-level radioactive waste (HLW) produced by nuclear power generation. The compacted bentonite buffer has a crucial role in protecting the disposal canister against the external impact and penetration of groundwater, so it has to satisfy the thermal-hydraulic-mechanical requirements. Even though there have been various researches on the investigation of thermal-hydraulic properties, few studies have been conducted to evaluate mechanical properties for the compacted bentonite buffer. For this reason, this paper conducted a series of unconfined compression tests and obtained mechanical properties such as unconfined compressive strength, elastic modulus, and void ratio of Korean compacted bentonite specimens with different water content and dry density values. The unconfined compressive strength and elastic modulus increased, and the Poisson's ratio decreased a little with increasing dry density. It showed that unconfined compressive strength and elastic modulus were proportional to dry density. However, there was not a remarkable correlation between mechanical properties and water content.
Keywords
Compacted bentonite buffer; Engineered barrier system; Unconfined compressive test;
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Times Cited By KSCI : 1  (Citation Analysis)
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