일반화된 Hoek-Brown 파괴조건식의 강도정수 a와 터널 보강깊이가 원형터널의 탄소성 거동에 미치는 영향 = Effect of Strength parameter a in the Generalized Hoek-Brown Failure Criterion and the Reinforcement Thickness on the Elasto-plastic Behavior of Circular Tunnel

다국어 초록 (Multilingual Abstract)

In the design stage of a tunnel, the wall convergence is commonly estimated through an elasto-plastic analysis of the tunnel, which has been a topic drawing many researcher`s attention so far. Despite its importance, however, the elasto-plastic behavior of a circular tunnel excavated in a generalized Hoek-Brown rockmass is still poorly understood. In this study, a simple numerical method based on Lee & Pietruszczak (2008) for the elasto-plastic analysis of a circular tunnel surrounded by reinforced annulus is proposed. It is assumed that the tunnel is excavated in a strain-softening rockmass obeying the generalized Hoek-Brown failure condition. The commercial code FLAC is used for the verification of the proposed method. The influence of the Hoek-Brown strength parameter a and the thickness of the reinforcement annulus on the elasto-plastic behavior around the tunnel was discussed by conducting some example analyses. The results show that the influence of these two parameters on the distribution of stresses and displacements is substantial.

참고문헌 (Reference)

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