TBM selection and performance prediction for shallow tunnels in interbedded sandstones and siltstones

摘要

In urban settings it has become fairly commonplace for infrastructure projects to use Tunnel Boring Machines for tunnel construction through both soil and rock. The selection and performance of a tunnel boring machine depends on geomechanical conditions within the proposed tunnel alignment. In interbedded sedimentary rocks, such as sandstones interbedded with clay and siltstones, the conditions at the face and within the walls of the tunnel behind can be highly variable, both along the tunnel and within the same tunnel cross section. Case studies in Calgary, AB are used to highlight the challenges faced and potential for improvements in the methodology.