Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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A Case Analysis on the Spalling Evaluation of the Deep Rock Mass and Pillar Spalling Modeling

고심도 암반의 스폴링 평가에 대한 사례 분석 및 광주 스폴링 모델링

  • Park, Seunghun (Dept. of Energy Resource Engineering, Inha University) ;
  • Kwon, Sangki (Dept. of Energy Resource Engineering, Inha University) ;
  • Lee, Changsoo (Radioactive Waste Disposal Research Division, Korea Atomic Energy Research Institute) ;
  • Lee, Jaewon (Radioactive Waste Disposal Research Division, Korea Atomic Energy Research Institute) ;
  • Yoon, Seok (Radioactive Waste Disposal Research Division, Korea Atomic Energy Research Institute) ;
  • Kim, Geon-Young (Radioactive Waste Disposal Research Division, Korea Atomic Energy Research Institute)
  • 박승훈 (인하대학교 에너지자원공학과) ;
  • 권상기 (인하대학교 에너지자원공학과) ;
  • 이창수 (한국원자력연구원 방사성폐기물처분연구부) ;
  • 이재원 (한국원자력연구원 방사성폐기물처분연구부) ;
  • 윤석 (한국원자력연구원 방사성폐기물처분연구부) ;
  • 김건영 (한국원자력연구원 방사성폐기물처분연구부)
  • Received : 2019.12.13
  • Accepted : 2020.01.08
  • Published : 2020.04.30
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Abstract

Globally, the deepening depth in the underground is a situation of the high interest for a purpose of the development of various facilities. The development of deep underground space should be based on the structural stability of rocks. Spalling is known to have an impact on the structural stability degradation in deep underground space. As an attempt to predict spalling, many researchers have proposed predicted conditions in accordance with stress states which occur around the tunnel, rock conditions, and types of rock. In addition, the analysis on spalling method has been verified by using computer modeling such as FLAC, EXAMINE, Insight 2D, UDEC and FRACOD, along with in-situ measurement results. In Canada URL (Underground Research Tunnel), CWFS model (Cohesion Weakening Frictional Strengthening) was used to precisely predict for the state of spalling, comparing spalling modeling. CWFS model has been identified as a reliable method for predicting such phenomena. This study aims to analyze several cases of spalling, and then make a comparison between the conditions for spalling occurrence and the predicted results of model CWFS. With this, it investigates the applicability of prediction of spalling, targeting pillar under deep depth condition.

전 세계적으로 지하의 고심도화는 다양한 시설 개발의 목적으로 관심도가 높은 상황이다. 고심도 지하공간의 개발은 암반의 구조적 안정성이 바탕이 되어야 한다. 고심도 지하공간에서는 스폴링이 구조적 안정성에 영향을 미치는 것으로 알려져 있다. 스폴링을 예측하기 위해서 많은 연구자들은 터널 주변에서 발생하는 응력상태, 암반상태 및 암종에 따라 제안하였다. 또한, 현지에서 측정된 결과와 FLAC, EXAMINE, UDEC, Insight 2D, FRACOD 등의 컴퓨터 모델링을 이용하여 스폴링 해석 방법에 대한 검증이 수행되었다. 캐나다 URL(Underground Research Tunnel)에서는 스폴링 현상에 대한 정확한 예측을 위해 CWFS(Cohesion Weakening Frictional Strengthening)모델을 제안하고 이를 비교 분석하였다. CWFS 모델은 스폴링 현상을 예측하는데 신뢰도 높은 방법으로 확인되었다. 본 연구에서는 고심도 암반에서의 스폴링 발생에 대한 사례들을 분석하고 스폴링 발생조건과 CWFS 모델의 예측 결과를 비교하였다. 이를 통해 고심도 조건에서의 광주를 대상으로 스폴링 예측에 대한 적용성을 검토하고자 하였다.

Keywords

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