FS has started the works for the excavation of the Cefalù Tunnel, in Sicily. The work is part of the doubling of the Cefalù-Castelbuono railway section on the Palermo-Messina line and is the largest of the three tunnels needed to upgrade the connection. The contract was awarded by Rete Ferroviaria Italiana (FS Italiane Group) to a group of companies headed by Toto General Construction, worth more than 370 million euro.
The new track has a total length of 12,3 kilometres, double track and almost entirely underground, and runs completely in a variant with respect to the old railway site.
The completion of section Ogliastrillo – Castelbuono, points out a FS press release - represents an extension of the Palermo Punta Raisi (already in operation) and will allow for the development of the transport that gravitates towards the Palermo hub as well as strengthening the connection between the Punta Raisi airport and the tourist hub of Cefalù, one of the most fascinating places in Sicily. The upgrading of the line will also allow for a better connection with Castelbuono, an ancient village in the Madonie and a renowned tourist destination.
Palermo-Messina, the maxi-mill Margherita in action for the tunnel
With the start of the works, the “Margherita” milling machine was put into motion Tunnel Boring Machine (TBM) which will excavate and line the more than 13 kilometers that make up the two parallel tunnels of the Cefalù Tunnel. 140 meters long, with a weight of 1650 tons and a total power of 5,6 MW, equal to approximately 8 Formula 1 engines, the mega-mill is equipped with a rotating head of 10 meters in diameter, equipped with over 60 tools excavator in steel, with which it is able to crush the rock.
Highly specialized personnel consisting of around 100 units will work on the excavation, mostly on board the machine, in three shifts a day, 24 days a week. Others will be engaged in auxiliary activities, for a total of over 7 workers overall employed on the site . With these numbers, an average daily progress of 7 meters is estimated, with peaks that may exceed 350 meters of tunnel excavated and lined. At this rate, the works in the tunnel are expected to be completed by November 16, while the completion of the doubling of the railway line is scheduled for 20.
Each tunnel tube will use around 8 tonnes of iron, 2,5 tonnes of iron fibers and around 77 cubic meters of concrete. Overall, the volume of earth excavated amounts to over 1 million cubic meters which will be largely reused, after characterization, for the re-environmentalisation of the former "Roccalupa" quarry.
The production of the ashlars that will cover the interior of the tunnel is already at full speed in the nearby prefabrication plant purposely built by Toto and exclusively dedicated to the project, where around 60 specialized workers are engaged. Overall, over 40 ashlars will be prefabricated here to cover the walls of the two tunnels.
In the meantime, the works for the construction of the remaining two tunnels excavated with the traditional method continue: S. Ambrogio (3975 m) with an advance of 68% and Malpertugio (138 m) with an advance of about 41%. The construction of the decks for the two viaducts located between the entrances of the S. Ambrogio and Cefalù tunnels is also underway.
