Face stability analysis of shallow shield tunneling in layered ground under seepage flow

This paper presents a limit equilibrium model for the shield face stability with special emphasis on the effects of ground heterogeneity and seepage flow. The model considers a new wedge mechanism whose inclination is capable of changing across soil layers to account for the spatial variation of soil mechanical properties. The limit equilibrium of the mechanism is established by using the method of slices, which considers horizontal arching...