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

  • 제22권4호
  • /
  • Pages.419-434
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  • 2020
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  • 2233-8292(pISSN)
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  • 2287-4747(eISSN)
한국터널지하공간학회 (Korean Tunnelling and Underground Space Association)
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처분 복합환경을 고려한 KURT 화강암의 Mazars 손상모델 평가

Evaluation of Mazars damage model of KURT granite under simulated coupled environment of geological disposal

  • 김진섭 (한국원자력연구원 방사성폐기물처분연구부) ;
  • 홍창호 (한국원자력연구원 방사성폐기물처분연구부) ;
  • 김건영 (한국원자력연구원 방사성폐기물처분연구부)
  • 투고 : 2020.06.09
  • 심사 : 2020.07.09
  • 발행 : 2020.07.31
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초록

본 연구에서는 처분장의 장기 건전성 평가모델을 확보하기 위해 한국원자력연구원 내 지하처분연구시설의 화강암을 대상으로 심층 처분복합환경을 모사한 암석시편의 Mazars 손상모델 상수를 측정하였다. 이를 위하여 실제 처분장 특성을 고려한 3가지 온도(15℃, 45℃, 75℃)와 건조/포화 조건에서 일축압축강도 및 간접인장강도 실험을 수행하였다. 최대유효인장변형률, At, Bt, Ac, Bc 등 주요 파라미터들은 콘크리트 대상으로 연구된 참고문헌의 값들과 차이를 보였으며 이는 암석과 콘크리트 시료의 탄성계수 차이 때문으로 판단된다. 시험결과 시료의 포화로 인해 Bt와 Bc의 값은 증가하였다. 또한 온도증가로 인해 최대 유효인장변형률과 Bt는 증가하였고 Bc는 감소하는 것을 확인하였다. 본 연구를 통해 도출된 손상모델은 한국원자력연구원 내에서 현재 개발 중인 Coupled Thermo-Hydro-Mechanical Damage 수치해석의 손상모델로 이용될 계획이다.

In this study, the damage parameters of Mazars model for KURT (KAERI Underground Research Tunnel) granite are measured form uniaxial compressive and Brazilian tests under the simulated coupled condition of a deep geological disposal. The tests are conducted in three different temperatures (15℃, 45℃, and 75℃) and dry/saturated conditions. Major model parameters such as maximum effective tensile strain (𝜖d0), At, Bt, Ac, and Bc differ from the typical reference values of concrete specimens. This is likely due to the difference in elastic modulus between rock and concrete. It is found that the saturation of specimens causes an increase in value of Bt and Bc while, the rise in temperature increases 𝜖d0 and Bt and decreases Bc. The damage model obtained from this study will be used as the primary input parameters in the development of coupled Thermo-Hydro-Mechanical Damage numerical model in KAERI.

키워드

참고문헌

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