The assembly and first laying of the “Expanded Sector” of the work has already been carried out. This tunnel has three sections of different sizes. We have designed a shell that fits the two larger ones and a second shell for the small one, while the transfer formwork is the same for all three sections. The works have begun with the larger section, the so-called Expanded Sector. Then a transition section will arrive with a fork and it will become two different tubes with the other two sections.The tunnel formwork moves on rails and has been designed to adapt it to the project’s reduced turning radii, project’s reduced turning radii ,levels and cambers variables.