ABSTRACT
A complex 3D numerical model of tunnelling in soft ground has been developed at Oxford University for the study of tunnelling-induced settlement damage to large masonry structures. The model includes procedures for simulating tunnel installation, including excavation, lining and ground loss. These procedures involve increments of tunnel installation where ground loss is simulated by shrinking the tunnel lining for that increment. This procedure is seen to be an effective approach for modelling tunnel installation, but it does lead to deformations that are non-uniform above the tunnel axis. This paper describes investigations of alternative methods for modelling tunnel installation using 3D finite element analysis.
