The lot T2C of the Line 15 is situated near Villiers Sur Marne in the south-eastern outskirts of the city. It includes: - two mechanized tunnels, principal and SMR lines, respectively 4.7 km and 2.2 km long; the main tunnel connects the Noisy Champs and Bry-Villiers- Champigny stations, while the SMR tunnel allows the connection between the main tunnel and the maintenance site; - an interconnection shaft of approximately 180 m (O807), 92 m of which are characterized by a traditional tunnel; - two TBMs launch shafts (O802P and O813P); - seven circular shafts used for evacuation and / or ventilation. Tasks: - Geotechnical design - Detailed and construction design of the underground cavern and of the shafts tunnel connections (by-pass). - Analysis of the effects induced by tunnels and station / shafts excavation on buildings - Design of driving parameters of TBM-EPB (Earth Pressure Balance)