At the beginning of February, one year after the start of the work, the site was marked by two milestones with the first excavations of the Casacastalda tunnel on 08/02/2022 and the installation of the steel span of the Calvario bridge.

The SS 318 is a crucial axis for East-West connections in Italy: leaving Perugia, in the direction of Ancona, it passes through the beautiful hilly countryside of Umbria, including that of the Valfabbrica municipality, after which the project is named. The project includes the construction of many civil works, in particular the Casacastalda (1545 m) and Picchiarella (874 m) two-lane tunnels, the 130-m Tre Vescovi viaduct and the 60-m Calvario bridge. These will add two lanes of traffic to the existing road.  

Excavation work of the 1.5km Casacastalda tunnel began on the eastern side and the Joint Venture Valfabbrica's team is now preparing a second front on the other side.

Theoretically, as long as the machines do not come up against large blocks of cohesive rock during the excavation, the operation should not require the use of explosives.

The tunnel is built using a traditional method, digging meter by meter and gradually installing steel beams. These form a metal ring in contact with the rock onto which concrete is sprayed, This first operation aims to secure the underground gallery in which the personnel and machines work. The final tunnel that will be built in this first safety tunnel. A tube within a tube. For the structure of the tunnel the technique called 'arco rovescio' is used. An arch is made on the upper part, supported by a lower arch. This requires the lower part to be poured quickly to hold the arches in the concrete. For the upper part, operations will

The Picchiarella tunnel, will be built using the same method and its excavation is expected to start in mid-2022.  The two tunnels will require 8,240 t of steel just for the consolidation of the excavation operations and a further 4,060 t for the reinforcement.    

For further information please click it/203 for tunnelbuilder archive. Visit https://www.stradeanas.it/ ,  https://www.besix.com/en/  and https://donatispa.it/ . 07/22.