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(사)한국터널지하공간학회

ISSN : 2233-8292

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Vol.14 No.6
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Numerical simulation for variations of water saturation in bentonite buffer under the effect of a rock joint using the TOUGH2 code

(사)한국터널지하공간학회 / (사)한국터널지하공간학회, (P)2233-8292; (E)2287-4747
2012, v.14 no.6, pp.575-593





& (2012). Numerical simulation for variations of water saturation in bentonite buffer under the effect of a rock joint using the TOUGH2 code. (사)한국터널지하공간학회, 14(6), 575-593.
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Abstract

This paper briefly introduces the scope and objectives of SKB Task 8, which is an international cooperative research project. In addition, the hydraulic behaviors of bentonite buffer focusing on the interactions between bentonite and a rock mass with a joint were investigated using TOUGH2 code as part of a sub-mission of Task 8a. The effects of a rock joint and high capillary pressure of bentonite on the re-saturation properties and pressure distribution in a buffer were identified and successfully incorporated in the TOUGH2 code. Based on the numerical results, it was found that the speed of re-saturation in bentonite surrounded by a rock mass with a joint is 2.5 to 12 times faster than that in a condition without a rock joint, while the degree of saturation in the lower part of the buffer material is generally higher than in the upper part in both the cases of with and without a joint. It can be anticipated that the results obtained from this study can be applied to an estimation of the full saturation time and a determination of optimum thickness with regard to the design of the bentonite buffer in a high level waste disposal system.

keywords
벤토나이트, 완충재, 포화도, TOUGH2, SKB Task 8, Bentonite, buffer material, saturation, TOUGH2, SKB Task 8

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