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

Korean Tunnelling and Underground Space Association (한국터널지하공간학회)
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Probabilistic rock mass classification using electrical resistivity - Theoretical approach of relationship between RMR and electrical resistivity-

전기비저항을 이용한 확률론적 암반분류 - RMR과 전기비저항 관계 이론 중심으로-

  • Ryu, Hee-Hwan (Power System Laboratory, KEPCO Research Institute) ;
  • Joo, Gun-Wook (Department of Civil and Environmental Engineering, KAIST) ;
  • Cho, Gye-Chun (Department of Civil and Environmental Engineering, KAIST) ;
  • Kim, Kyoung-Yul (Power System Laboratory, KEPCO Research Institute) ;
  • Lim, Young-Duck (Transmission Project Department, Project Development Division, KEPCO)
  • 류희환 (한전전력연구원 파워시스템연구소) ;
  • 주건욱 (KAIST 건설 및 환경공학과) ;
  • 조계춘 (KAIST 건설 및 환경공학과) ;
  • 김경열 (한전전력연구원 파워시스템연구소) ;
  • 임영덕 (한국전력공사 개발사업본부 송변전개발처)
  • Received : 2013.03.04
  • Accepted : 2013.03.15
  • Published : 2013.03.28
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Abstract

It is very important to understand the condition of the surround rock for the successful construction of underground space. Representative methods of estimating the rock mass condition are RMR method and Q-system, and they are applied on design, construction, and maintenance. However, many problems with the accuracy of the measurement method and the subjective viewpoint are questioned continuously, so many researchers have been studied for estimating rock condition from various methods. Most of them show only the local relation and a tendency between site investigation data and rock conditions. In this paper, the relationship between RMR method and electrical resistivity is deducted using the analytical equation derived theoretically from electric field analysis on jointed rock mass. And also, probabilistic relationship between RMR method and electrical resistivity is deducted for the increase of accuracy. If a suggested method is applied with the conventional method for estimating the rock condition, it will be helpful to estimate RMR values on the field.

성공적인 지하공간 건설을 위해서는 주변 암반의 상태를 정확히 파악하는 것이 매우 중요하다. 암반의 상태를 평가하는 방법 중에 대표적인 방법으로는 RMR 방법과 Q-system이 있으며, 설계, 시공, 유지관리 등에 적용되고 있다. 하지만 주관적인 시각과 측정 방법의 정확성 문제에 지속적으로 의문이 제기되어 많은 연구자들이 여러 방법을 통해 암반을 평가하고자 연구를 수행하고 있으나, 대부분의 방법이 국한적으로 지반조사 결과와 암반상태를 상관 맺거나 경향성만 보여주고 있다. 본 논문에서는 절리가 존재하는 암반에서 이론적으로 전기장 해석을 하여 유도된 이론식으로 부터 RMR과 전기비저항의 관계를 도출하였다. 또한, 확률론적 접근을 통해, 보다 신뢰성 있는 RMR과 전기비저항 관계를 획득하였다. 기존에 사용되고 있는 방법과 더불어 제시된 방법을 현장에 적용한다면, 현장에서 RMR을 평가하는데 도움을 줄 수 있을 것으로 판단된다.

Keywords

References

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