Journal of Korean Tunnelling and Underground Space Association (한국터널지하공간학회 논문집)

Korean Tunnelling and Underground Space Association (한국터널지하공간학회)
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Development of hydro-mechanical-damage coupled model for low to intermediate radioactive waste disposal concrete silos

방사성폐기물 처분 사일로의 손상연동 수리-역학 복합거동 해석모델 개발

  • Ji-Won Kim (Disposal Performance Demonstration R&D Division, Korea Atomic Energy Research Institute) ;
  • Chang-Ho Hong (Disposal Performance Demonstration R&D Division, Korea Atomic Energy Research Institute) ;
  • Jin-Seop Kim (Disposal Performance Demonstration R&D Division, Korea Atomic Energy Research Institute) ;
  • Sinhang Kang (Dept. of Civil and Environment Engineering, Hannam University)
  • 김지원 (한국원자력연구원 저장처분실증연구부) ;
  • 홍창호 (한국원자력연구원 저장처분실증연구부) ;
  • 김진섭 (한국원자력연구원 저장처분실증연구부) ;
  • 강신항 (한남대학교 토목환경공학전공)
  • Received : 2024.03.04
  • Accepted : 2024.04.26
  • Published : 2024.05.31
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Abstract

In this study, a hydro-mechanical-damage coupled analysis model was developed to evaluate the structural safety of radioactive waste disposal structures. The Mazars damage model, widely used to model the fracture behavior of brittle materials such as rocks or concrete, was coupled with conventional hydro-mechanical analysis and the developed model was verified via theoretical solutions from literature. To derive the numerical input values for damage-coupled analysis, uniaxial compressive strength and Brazilian tensile strength tests were performed on concrete samples made using the mix ratio of the disposal concrete silo cured under dry and saturated conditions. The input factors derived from the laboratory-scale experiments were applied to a two-dimensional finite element model of the concrete silos at the Wolseong Nuclear Environmental Management Center in Gyeongju and numerical analysis was conducted to analyze the effects of damage consideration, analysis technique, and waste loading conditions. The hydro-mechanical-damage coupled model developed in this study will be applied to the long-term behavior and stability analysis of deep geological repositories for high-level radioactive waste disposal.

본 연구에서는 방사성폐기물 처분구조물의 안전성 및 건전성 평가를 위해 손상연동 수리-역학 복합 거동 해석 모델을 개발하였다. 콘크리트나 암반과 같은 취성재료의 파괴 모사에 널리 사용되는 Mazars 손상 모델을 선정하여 수리-역학 해석에 연동하였고, 예제 및 정해를 기반으로 개발된 해석 모델을 검증하였다. 개발된 해석 모델의 손상 입력 인자를 도출하기 위해 처분구조물 콘크리트 배합비로 제작한 시료를 대상으로 건조/포화 양생 조건에서 일축압축강도 및 간접인장강도 시험을 수행하였다. 실내 시험을 통해 도출한 입력 인자는 경주 월성 원자력 환경관리센터의 동굴처분 콘크리트 사일로를 모사한 2차원 유한요소해석에 적용하여 손상 고려 유무, 해석 기법 및 폐기물 하중 재하 조건에 따른 영향을 분석하였다. 연구를 통해 개발된 수리-역학-손상 모델은 향후 고준위 방사성폐기물 처분을 위한 심층처분장의 장기 거동 및 안정성 해석에 적용할 계획이다.

Keywords

Acknowledgement

본 연구는 사용후핵연료관리핵심기술개발사업단 및 한국연구재단의 지원(NRF-2021M2E1A1085193, NRF-2022M2E3A3015608)으로 수행되었습니다. 이에 감사드립니다.

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