The work, whose construction began in September 2016 and finished in September 2018, constitutes the third and last lot of an organic complex of bridges and tunnels for the enhancement and modernization of the public roads connecting the tourist area of the Val d 'Ega with the Brenner motorway and the city of Bolzano.
The new works make it possible to by-pass a particularly inaccessible area of the valley, where the old road ran along the bottom of a narrow gorge with high unstable rock faces overhanging the road.
The 3rd Lot represents the completion of the previous two lots (already completed) that develop starting from the Cardano junction on the S.S.12 and more precisely:
• Lot 1 - Cardano Nord junction and Cornedo tunnel with a length of 1,148 m;
• Lot 2 - construction of Bridge 1, the Campegno tunnel with a length of 1,427 m, Bridge 2 and the artificial Tschungg tunnel with a length of 100 m.
The route of the 3rd Lot starts from the portal of the Tschungg artificial tunnel (pk 2 + 833) of Lot 2 (already built), crosses the Ega stream with a bridge of 23.39 m of span (called bridge 3) and develops in gallery (called Contrada 1) for a length of 367.03 m. After going through the Contrada 1 "tunnel, the route develops for an open stretch of about 40 m, passing the current headquarters of the S.S. 241 and, again, the Ega stream with a new bridge (Ponte 4) of 25.21 m of light to re-enter the tunnel (Contrada 2 tunnel, 256.55 m). At the end of the Contrada 2 tunnel, the route develops outdoors to rejoin the site of the old S.S. 241 at the p.k. 3 + 610.
From this progressive road, for a section of about 350 m, the new route follows the old one, but with corrections and widening of the carriageway mainly overhanging towards the valley.
The safety equipment of the two tunnels of the 3rd Lot, in consideration of the contiguity with the two long tunnels of the previous lots, were designed considering the entire "chain of galleries ".
Therefore, given the traffic volume (equal to approximately 2,900 v / d per direction of travel, division by direction 50% -50%) and given the length of the "chain of tunnels" (equal to approximately 3.5 km), pursuant to art. 60 of the D.P.P. n ° 28/2006, the safety equipment made are those of class A. All the systems of the galleries of the 3rd Lot are controlled by a supervision and control system that interfaces with that of the tunnels of the previous lots: the two systems "communicate" continuously thanks to a software that has been programmed according to all the possible combinations of the emergency scenarios that could occur inside the tunnels. The two bridges (Bridge 3 and Bridge 4) have a single span with a mixed structure, consisting of Cor-Ten steel beams with a collaborating reinforced concrete slab, made by laying self-supporting prefabricated slabs and integrating casting on site. Bridge 4, located between the two tunnels, also has a roof consisting of ribbed Cor-Ten steel sheet, with longitudinal ribs, which constitutes the main load-bearing structure, stiffened by crossbeams with the function of distributing loads. The self-supporting structure, with a span of 31 m, rests on the portals of the two galleries
