ABSTRACT
Standard tunnel design in rock focuses on the ultimate limit state of the rock mass and lining separately. Indeed, the consideration of the rock mass is often not significant in tunneling unless it causes large deformations on neighboring structures or on the surface. Therefore, ultimate limit state considerations of the lining itself aim on the capability to resist the combined actions of axial, shear and bending at a first conservative level. In a second level, its interaction with the surrounding rock mass is evaluated and in a third level, deformations are taken into consideration.
