A 3D Finite Element Simulation of a Shield Tunnel in Weathered Singapore Bukit Timah Granite

摘要

Both two- and three-dimensional finite element analyses of an Earth Pressure Balance (EPB) shieldrntunnel are carried out. For the back-analyses the contract T-06 (Queensway Tunnel) of the DeeprnTunnel Sewerage System, in Singapore is considered. Soil parameters from laboratory tests are usedrnand the results are compared to measurements from site. For the two-dimensional analyses a tunnelrncontraction approach is applied and for the three-dimensional analyses a step-by-step contractionrnprocedure for shield tunnels is proposed in this paper. To obtain good results of numerical analyses itrnis important to understand the material behaviour of the soil, which implies to choose an appropriaternmaterial model. In this paper the non-linear behaviour of weathered Bukit Timah Granite is modelledrnrealistically using an advanced soil model.