ABSTRACT
The simulation served to validate a parametric study investigating the long-term behaviour of twin tunnels; this study is described in Laver (2010).
The analyses also provided an opportunity to trial a new fissure model, outlined in Laver & Soga (2011). The fissure model was developed in response to two key observations from recent laboratory test data on London Clay (Hight et al. 2007): softening on fissures in triaxial extension tests, and softer behaviour for torsional shearing modes in the Hollow Cylinder Apparatus (HCA).
