In the world the increasing need of the improvement of the transportation infrastructures led to the construction of twin tunnels at shallow depths. For this reason, the aim of this thesis is to analyse the interaction between two overlapped tunnels changing the construction process. To do that, the project of the metro M5 of Bucharest is taken as reference for the developed 3D and 2D numerical model. The FEM analysis are performed using the software MIDAS FEA NX and PLAXIS 2D. As first, the segmental tunnel lining is described considering all the parts and materials which compose it, in order to understand the answer of the model to the change of the excavation sequence.