Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Fast Analysis of Rock Block Behavior on Underground Opening considering Geostatic Stress Conditions

지체응력조건을 고려한 지하공동 주변부 암석블록의 신속한 거동 안정성 분석

  • Kang, Il-Seok (Seoul National University, Department of Energy Systems Engineering) ;
  • Song, Jae-Joon (Seoul National University, Department of Energy Systems Engineering)
  • 강일석 (서울대학교 에너지시스템공학부) ;
  • 송재준 (서울대학교 에너지시스템공학부)
  • Received : 2019.02.11
  • Accepted : 2019.02.20
  • Published : 2019.02.28
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Abstract

Behavior of a rock block consisting of rock joints during excavation of an underground opening is an important factor for the mechanical stability of the opening. In this study, the behavior of a rock block under different geostatic stress and joint property conditions was analyzed quantitatively. The behavior of the rock block analyzed by 3DEC numerical analysis was compared with that of the theoretical calculation, and the error between the theoretical value and the numerical analysis result was analyzed under various geostatic stress and joint property conditions. The result of the stability analysis of a rock block showed less than 5% of error with numerical simulation result, which verified the applicability of the purposed analytic solution.

지하공동의 굴착 과정에서 암반 절리로 인해 생성되는 암석블록의 거동 여부는 지하공동의 역학적 안정성에 있어서 중요한 요소이다. 본 연구에서는 대심도 지하공동 조건 하에서 지체응력 및 절리물성 조건에 따른 암석블록의 거동 안정성을 정량적으로 분석하였다. 이론적으로 계산된 암석블록의 거동조건과 3DEC 수치해석을 통해 분석된 암석블록의 거동양상을 비교하여, 이론값과 수치해석 결과간의 오차를 지체응력 및 절리물성 조건에 따라 분석하였다. 암석블록의 거동 안정성 분석을 수행한 결과는 수치해석 결과와 비교할 때 약 5% 이하의 오차를 보여 본 연구에서 제시한 이론적 방법론의 적용가능성을 검증하였다.

Keywords

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Fig. 1. Three dimensional model of underground opening and rock block

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Fig. 2. Regression analysis results of the coefficient of stress transmission ratio (M)

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Fig. 3. Regression analysis results of the coefficient of stress transmission ratio (N)

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Fig. 4. Verification results under different stress and joint conditions

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Fig. 5. Locations of rock blocks in verification tests

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Fig. 6. Verification of suggested method under different block location

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Fig. 6. Verification of suggested method under different block location (Continued)

Table 1. Mechanical properties of rock mass used in this study (Kim, 2015)

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Table 2. Mechanical properties of rock joints used in 3DEC simulation (Itasca, 2014)

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Table 3. Joint stiffness conditions used in 3DEC simulation

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Table 4. Analysis results of critical state pulling force in 3DEC

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Table 4. Analysis results of critical state pulling force in 3DEC (Continued)

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References

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