Shallow tunnel face stability considering pore water pressure in non-homogeneous and anisotropic soils

• Published in: Computers and geotechnics Vol. 116; p. 103205
• Main Authors: Chen, Guang-hui, Zou, Jin-feng, Chen, Jia-qi
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.12.2019; Elsevier BV
• Subjects: Analysis; Anisotropic; Anisotropic soils; Anisotropy; Discretization technique; Failure analysis; Failure mechanisms; Finite element method; Hydrostatic pressure; Limit analysis; Non-homogeneous; Nonuniform ground surcharge; Pore pressure; Pore water; Pore water pressure; Shallow tunnels; Soil properties; Soil stability; Stability analysis; Tunnels; Upper bound theorem; Upper bounds; Water pressure; Nonuniform ground surcharge; Non-homogeneous; Shallow tunnels; Anisotropic; Upper bound theorem; Pore water pressure; Discretization technique
• ISSN: 0266-352X; 1873-7633
• DOI: 10.1016/j.compgeo.2019.103205

An improved approach for the face stability analysis of shallow tunnels in non-homogeneous and anisotropic soil is developed in this study. Based on the discretization technique, an advanced passive failure mechanism is proposed to determine the critical support pressure of the tunnel face in the framework of the upper bound theorem. To better estimate the tunnel face stability, the effects of the pore water pressure and nonuniform ground surcharge on the critical support pressure of the tunnel face are also incorporated in the non-homogeneous and anisotropic soil properties. Then the optimal supporting forces obtained from the proposed failure mechanism are validated by those from the conventional limit analysis model in homogeneous soil and finite element limit analysis in homogeneous and non-homogeneous soils.