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Publisher Summary There are many examples of transportation projects involving underground construction of shallow tunnels in soft ground conditions within congested urban environments. One of the key design criteria for such projects is to assess the impacts of the proposed tunnel construction methods (either by tunnel boring machines or by open-face excavation methods) on existing facilities and to control the construction procedures to limit deformations within the surrounding soil. Realistic modeling of these problems represents a very challenging problem that must typically simulate the following five conditions: (1) the complex sequence of excavation and support conditions at the advancing tunnel heading ; (2) the interaction between soil and the structural lining system; (3) the nonlinear behavior of the soil; (4) the coupled effects of groundwater seepage and deformations; and (5) ancillary activities ranging from grouting (either around the lining or within the soil mass) to soil nailing (reinforcement ahead of excavated face). Although many of these processes clearly require modeling in three dimensions, the great majority of analyses reported to date represent tunnel constructions using simplified plane strain models (using artificial concepts such as equivalent ground loss to represent 3D effects around the tunnel heading).