Upper and lower bounds for three-dimensional undrained stability of shallow tunnels

This paper deals with the determination of upper and lower bounds for the three-dimensional undrained stability of shallow tunnels. The tunnel is circular and a distance between its face and its lining is considered. The soil shear strength is modeled using the Tresca criterion. Results of the upper and lower bounds of the stability number are presented, for several geometrical and resistance configurations and their comparison with previous results is made, showing the clear improvement obtained. Finally, equations approaching the stability number are proposed.

Automated summary

This paper discusses the determination of upper and lower bounds for three-dimensional undrained stability of shallow tunnels, with the soil shear strength modeled using the Tresca criterion. Results show a clear improvement in stability number bounds for various geometrical and resistance configurations compared to previous findings. Proposed equations provide an approach to estimating the stability number.