Tunnels excavation using Tunnelling Boring Machines (TBM,EPB, Mixshield etc) has grown up a lot in the last decade. One of the most serious challenges to cope for tunnelling machines is the crossing of the reinforced - concrete structures of launching and recovery shafts as well as stations built along the TBM route. Very often such structures, which are built to a great depth, are usually reinforced with large amounts of steel rebars in order to stand strong ground and water pressure. Breaking of these walls by the TBM is impossible because it would damage its cutting tools; for this reason it has to be done manually, by breaking the concrete wall and cutting the reinforcing steel bars inside it. This operation requires a lot of time and it can be dangerous, overall in presence of groundwater pressures. The more the thickness of the wall is reduced, the more the water counter-pressure can suddenly break into the launching shafts, causing water flooding inside it. This is the reason why nowaday a new reinforcing technique offered by Glass Fibre Reinforced Polymer rebars (Soft Eye Technique) is more and more adopted. The technique consists in substituting the internal steel reinforcing bars of the wall with GFRP bars and stirrups, which have a high tensile strength but low shear strength, therefore allowing the TBM to bore through the wall section easily and without damaging the cutting tools of the machine. Commonly, a section (cage) of the wall corresponding to the dimension of the TBM shield is reinforced using GFRP, leaving the upper and the lower sections of the cage built with steel rebars. The two steel sections are than connected to the GFRP cage by overlapping steel and glass fibre bars. Nowadays the soft-eye technique is used in several projects all around the world and applied not only for diaphragm walls but also as reinforcement for piles and for complex concrete structures.