Analysis of tunnel face stability with non-linear failure criterion under the pore water pressure

Abstract

In this work, the stability of a shield tunnel face under pore water pressures is examined by combining the non-linear Mohr-Coulomb failure criterion in the framework of the kinematic approach of limit analysis. The non-linear Mohr-Coulomb failure criterion represented by the tangent technique in combination of the pore water pressure distribution calculated by the mesh dividing optimization technology are incorporated into the 3D rotational failure mechanism to assess the critical support pressure of a tunnel face for the first time. Based on the proposed method, parametric studies are performed by giving design charts to study the effect of model parameters on the calculated critical support pressure. In these charts, comparisons with results from the linear Mohr-Coulomb failure criterion are used to verify the proposed method. Finally, the influence of the non-linear coefficient on the feature of the 3D rotational failure mechanism is presented.