Evaluation on the Discontinuity Characteristics and Rock Quality Designations of the Rock Mass around KURT

Seungbeom Choi; Kyung-Woo Park; Yong-Ki Lee

doi:10.7474/TUS.2022.32.6.397

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2022 Vol.32, Issue 6 Preview Page Next Page

Technical Note

Evaluation on the Discontinuity Characteristics and Rock Quality Designations of the Rock Mass around KURT KURT 주변 암반에 대한 불연속면 분포와 암질지수 평가

31 December 2022. pp. 397-410

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Abstract

The safety of the disposal repository for high level radioactive waste should be guaranteed for a quite long period so that the precise evaluations are required. The site characteristics of the discontinuities are essential part of the safe repository design including engineered barrier and natural barrier systems. The discontinuities act like weak planes and at the same time, they act as flow paths so that their features should be investigated thoroughly. RQD (Rock Quality Designation) is one of the most widely applied characterizing methods due to its simplicity, however, modified designations have been proposed because RQD has some drawbacks, such as its directivity and dependence on the threshold length. This study aims to evaluate the applicability of the modified designations by applying them to the rock mass around KURT and to produce fundamental database that will be utilized in future studies.

Keywords

Discontinuity distribution

Modified rock quality designation

KURT

Applicability

불연속면 분포, 수정 암질 지수 KURT, 적용성 평가방사성폐기물처분장은 장기간에 걸쳐 그 안전성이 보장되어야 하며, 따라서 정밀한 수준의 안정성 평가가 수행되어야 한다. 처분장 부지의 불연속면 특성 평가는 공학적방벽과 천연방벽을 포함한 처분장의 안전한 설계에 있어 매우 중요한 요소이다. 암반 불연속면은 역학적으로는 연약면으로 작용하며 수리적으로는 지하수 유동의 통로가 되기 때문에 그 분포와 특성에 대한 정밀한 조사가 요구된다. 다양한 불연속면 특성화 방안 중 암질지수(RQD)는 그 편이성으로 인해 널리 적용되어왔으나, 방향성이 있고, 측정 기준 길이의 영향을 받는 등 적용상의 한계가 있기 때문에, 이를 보완한 형태의 수정 암질지수들이 제안되어왔다. 본 논문은 KURT 주변 암반의 불연속면 정보를 활용하여 수정 암질지수들의 적용성을 평가하고, 동시에 해당 암반의 불연속면 특성을 평가하여 향후 연구에 활용할 수 있는 기반자료를 생성하기 위해 작성되었다.

키워드

불연속면 분포

수정 암질 지수

KURT

적용성

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Information

Publisher :Korean Society for Rock Mechanics and Rock Engineering
Publisher(Ko) :한국암반공학회
Journal Title :Tunnel and Underground Space
Journal Title(Ko) :터널과 지하공간
Volume : 32
No :6
Pages :397-410
Received Date : 2022-12-07
Revised Date : 2022-12-12
Accepted Date : 2022-12-13
DOI :https://doi.org/10.7474/TUS.2022.32.6.397

Tunnel and Underground Space ISSN:1225-1275(Print) 2287-1748(Online) 터널과 지하공간

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