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2026 Vol.36, Issue 3 Preview Page

Original Article

Evaluation of Thermal Properties of Various Deep Crystalline Rocks for Site Selection and Design of High-Level Radioactive Waste Deep Disposal in Korea

고준위방사성폐기물 부지선정과 심층처분시설 설계를 위한 국내 심부 결정질암의 열물성 평가

Jaewon Lee1
,
Sangbeen Lee2
,
Jongwon Jung3
,
Ki Seog Kim4
,
Junhyung Choi5
,
Dae-Sung Cheon6*
이 재원1
,
이 상빈2
,
정 종원3
,
김 기석4
,
최 준형5
,
천 대성6*
1Master’s Student, School of Civil engineering, Chungbuk National University
2Combined MD-Ph.D Student, School of Civil engineering, Chungbuk National University
3Professor, School of Civil engineering, Chungbuk National University
4CEO, Heesong Geotek, CO., LTD.
5Senior Engineer, Deep Geological Disposal and Energy Storage Research Center, Korea Institute of Geoscience and Mineral Resources
6Principal Researcher, Deep Geological Disposal and Energy Storage Research Center, Korea Institute of Geoscience and Mineral Resources
1충북대학교 토목공학부 석사과정
2충북대학교 토목공학부 석박사통합과정
3충북대학교 토목공학부 교수
4희송지오텍 대표이사
5한국지질자원연구원 방폐물심층처분연구센터 선임기술원
6한국지질자원연구원 방폐물심층처분연구센터 책임연구원
*Corresponding Author
30 June 2026. pp. 277-291
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Abstract

Currently, deep disposal is being promoted in Korea for the permanent disposal of high-level radioactive waste (HLW) within deep rock formations. The thermal properties of the rock mass are critical factors that determine the spacing between disposal holes and tunnels, as well as the total volume of the disposal facility. Therefore, these properties must be evaluated to ensure the economic feasibility and suitability of a disposal site. However, measured data on the thermal properties of deep rock formations in Korea remain scarce. Crystalline rock considered as a host rock in deep disposal repository includes granite and gneiss. In this study, deep rock samples were collected from Hongcheon and Hadong, which are located in gneiss regions. Thermal properties, including thermal conductivity, specific heat, and thermal diffusivity were determined using the Transient plane source method (TPS), while the coefficient of thermal expansion was measured using strain gauges. Furthermore, X-ray diffraction (XRD) analysis confirmed that rock-forming minerals are key factors influencing thermal conductivity. Both the measured values from this study and the existing literature data exhibited a proportional relationship between thermal conductivity and thermal diffusivity. Furthermore, it was confirmed that the analysis of thermal conductivity based on quartz content yielded the highest accuracy. The findings of this study are expected to serve as significant fundamental data for the site selection and design processes of deep disposal facilities in Korea.

Keywords
Crystalline rock
Thermal property
HLW
TPS
Deep disposal

현재 국내에서는 고준위방사성폐기물을 심부 암반층에 영구적으로 처분하는 심층 처분이 추진되고 있다. 암반의 열물성은 심층 처분 시 처분공 간격과 처분터널 간격, 심층처분시설 체적 등을 결정하는 주요한 인자로서 이는 처분부지 및 경제성 확보를 위해 필수적으로 고려되어야 한다. 하지만 국내에서는 심부 암반의 열물성을 측정한 사례가 드물다. 심층처분시설의 모암으로 고려되는 결정질암으로 화강암과 편마암 등이 있으며, 본 연구에서는 편마암 지대에 위치한 홍천과 하동에서 심부 암석을 채취하여 연구를 수행하였다. 열물성은 TPS를 사용하여 열전도도, 비열, 열확산율을 산출하였고, 스트레인 게이지를 사용하여 열팽창계수를 측정한 뒤 결정질암인 화강암을 중심으로 국내외 문헌과 비교하였다. XRD 분석을 통해 조암광물과 열전도도의 상관성을 분석하였다. 본 연구 측정값 및 문헌값 모두 열전도도에 따른 열확산율이 비례 관계를 보였다. 석영 함량에 따른 열전도도 분석이 가장 높은 정확도를 갖는 것으로 확인하였다. 본 연구 결과는 국내 고준위방사성폐기물 부지 선정과 심층처분시설 설계 과정에 있어 중요한 기초 자료로 활용될 것으로 기대된다.

키워드
결정질암
열물성
HLW
TPS
심층처분
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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 : 36
  • No :3
  • Pages :277-291
  • Received Date : 2026-05-11
  • Revised Date : 2026-06-17
  • Accepted Date : 2026-06-18
  • DOI :https://doi.org/10.7474/TUS.2026.36.3.277
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