Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Study of the Static Shear Behaviors of Artificial Jointed Rock Specimens Utilizing a Compact CNS Shear Box

Compact CNS shear box를 활용한 모의 절리암석시료의 정적 전단 거동에 관한 연구

  • Hanlim Kim (Department of Mineral Resources & Energy Engineering, Jeonbuk National University) ;
  • Gyeongjo Min (Department of Mineral Resources & Energy Engineering, Jeonbuk National University) ;
  • Gyeonggyu Kim (Department of Energy Storage & Conversion Engineering of Graduate School, Jeonbuk National University) ;
  • Youngjun Kim (Department of Energy Storage & Conversion Engineering of Graduate School, Jeonbuk National University) ;
  • Kyungjae Yun (Agency for Defense Development) ;
  • Jusuk Yang (Agency for Defense Development) ;
  • Sangho Bae (Agency for Defense Development) ;
  • Sangho Cho (Department of Mineral Resources & Energy Engineering, Jeonbuk National University)
  • 김한림 (전북대학교 자원.에너지공학과) ;
  • 민경조 (전북대학교 자원.에너지공학과) ;
  • 김경규 (전북대학교 에너지.저장/변환공학과) ;
  • 김영준 (전북대학교 에너지.저장/변환공학과) ;
  • 윤경재 (국방과학연구소) ;
  • 양주석 (국방과학연구소) ;
  • 배상호 (국방과학연구소) ;
  • 조상호 (전북대학교 자원.에너지공학과/에너지저장변환공학과)
  • Received : 2023.12.11
  • Accepted : 2023.12.22
  • Published : 2023.12.31
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Abstract

In this study, the effectiveness and applicability of a newly designed Compact CNS shear box for conducting direct shear tests on jointed rock specimens were investigated. CNS joint shear tests were conducted on jointed rocks with Artificially generated roughness while varying the fracture surface roughness coefficient and initial normal stress conditions. In addition, displacement data were validated by Digital image correlation analysis, fracture patterns were observed, and comparative analysis was conducted with previously studied shear behavior prediction models. Furthermore, the accuracy of the displacement data was confirmed through DIC analysis, the fracture patterns were observed, and the shear properties obtained from the tests were compared with existing models that predict shear behavior. The findings exhibited a strong correlation with specific established empirical models for predicting shear behavior. Furthermore, the potential linkage between the characteristics of shear behavior and fracture patterns was deliberated. In conclusion, the CNS shear box was shown to be applicable and effective in providing data on the shear characteristics of the joint.

본 연구에서는 절리면 암석 시료에 대한 직접 전단시험을 수행하기 위해 새로 고안된 Compact CNS shear box의 성능과 적용 가능성에 대해 조사하였다. 정적 CNS 절리면 직접 전단시험은 인공적으로 거칠기를 생성한 절리 암석을 대상으로 실시하였으며 절리면 거칠기 계수 및 초기 수직응력 조건을 변화시키면서 수행하였다. 또한, DIC 분석을 통해 변위 데이터 검증 및 파괴 패턴을 관찰하였고 실험으로부터 도출된 전단 특성들을 기존에 연구되었던 전단 거동 예측 모델들과 비교분석하였다. 그 결과 기존의 특정 경험적 전단 거동 예측 모델과 높은 상관관계를 나타내는 것을 확인하였으며 전단 거동 특성이 파괴 패턴과 관련이 있을 가능성에 대해 고찰하였다. 결론적으로, 절리면 전단 특성에 대한 데이터를 제공하는데 있어서 CNS 전단 박스의 적용 가능성과 효과를 입증하였다.

Keywords

Acknowledgement

이 논문은 2020년 정부(방위사업청)의 재원으로 국방과학연구소의 지원을 받아 수행된 연구임(UE201046GD)

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