불연속성 암반에서의 터널의 암반블럭 평가를 위한 신 정보화설계시공법

New Observational Design and Construction Method for Rock Block Evaluation of Tunnels in Discontinuous Rock Masses

  • 황재윤 (부산대학교 공과대학 토목공학과)
  • 발행 : 2006.02.01

초록

실제 암반에는 단층, 절리, 층리, 균열, 단열, 편리, 벽개 등의 불연속면이 많이 포함되어 있다. 따라서, 불연속면이 암반구조물의 거동을 좌우하고 있다. 암반구조의 복잡성으로 인해 사전에 예측 할 수 없었던 암반의 붕락이 발생하여, 붕락대책에 막대한 비용과 시간을 낭비하는 사례가 많다. 암반 불연속면의 복잡성을 사전 조사단계에서 충분히 파악하거나 대책을 수립하는 것은 어렵다. 최근 터널의 정보화 설계시공이 중요시되어지고 있다. 본 논문에서는 불연속성 암반에서의 터널의 신 정보화 설계시공법을 제안하고, 현지에서 관찰한 불연속면 정보를 근거로 하여 실제 터널현장에 적용했다. 실제 터널현장에 있어서, 터널의 신 정보화 설계시공법을 위해서 새롭게 개발한 수치해석 프로그램을 사용하여 정확한 키블럭 추출이 가능하였다. 사용하기 쉬운 사용자 인터페이스를 가지고 있는 본 컴퓨터 시뮬레이션 기법은 암반블럭의 안정성 계산뿐만 아니라 추가 보강대책공의 설계도 가능하다. 터널 굴착중에 키블럭을 확인하므로써, 제안한 신 정보화 설계시공법의 유효성에 대한 검증을 하였다.

Rock masses in nature include various rock discontinuities such as faults, joints, bedding planes, fractures, cracks, schistosities, and cleavages. The behavior of rock structures, therefore, is mainly controlled by various rock discontinuities. In many tunnels, enormous cost and time are consumed to cope with the failing or sliding of rock blocks, which cannot be predicted because of the complexity of rock discontinuities. It is difficult to estimate the properties of rock masses before the rock excavation. The observational design and construction method of tunnels in rock masses is becoming important recently. In this paper, a new observational design and construction method for rock block evaluation of tunnels in discontinuous rock masses is proposed, and then applied to the tunnel based on actual rock discontinuity information observed in the field. It is possible to detect key blocks all along the tunnel exactly by using the numerical analysis program developed far the new observational design and construction method. This computer simulation method with user-friendly interfaces can calculate not only the stability of rock blocks but also the design of supplementary supports. The effectiveness of the proposed observational design and construction method has been verified by the confirmation of key block during the enlargement excavation.

키워드

참고문헌

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