About the author:

1. China Railway First Group Co., Ltd., Xi’an,Shaanxi 710054, China; 2. School of Civil Engineering,Zhengzhou University, Zhengzhou,Henan 450001, China; 3. School of Civil Engineering,Central South University, Changsha,Hunan 410075,China

Abstract:

Geotechnical failure under external forces is mostly characterized by nonlinear feature. Fewworks investigate the face stability of horseshoe shield tunnel considering nonlinear failure feature. Basedon this, the nonlinear failure feature is denoted by nonlinear Mohr-Coulomb failure criterion. Thehorseshoe rotational failure model is developed by improving the circular rotational failure model. In thecontext of limit analysis method, a nonlinear stability analysis model for horseshoe shield tunnel face isproposed by combining the nonlinear Mohr-Coulomb failure criterion and horseshoe rotational failuremodel. The results show that: Neglecting the nonlinear feature will result in unsafe estimations for tunnelface stability; Stability analysis results of horseshoe tunnel face are close to the those for circular tunnelface with equivalent area. The limit support pressure and three-dimensional failure surface for circulartunnel face can be utilized to assess the stability of horseshoe tunnel face with equivalent area.