In this study the interaction between the ground and a reinforced-concrete building during tunnelling is investigated by a fully coupled three-dimensional approach using the Finite Element code PLAXIS 3D. The excavation of the Milan underground new line 5 by an earth pressure balance (EPB) machine in granular soils is taken as reference for tunnel characteristics and ground conditions. A number of ideal multi-storey reinforced-concrete buildings with appropriate stiffness and weight is examined, all of them being located in a symmetric position with respect to the tunnel. The analysis is also extended to highlight the stiffening contribution of the infill external panels of the structures, schematised as equivalent cross-bracings, on the transversal and longitudinal settlement profiles. The attention is also focused on the evolving response shown by the building columns, evaluated in terms of normal compression forces, during the excavation process.