Projects: Underground engineering
Isca Pantanelle - Polla road
Main features of 'D'Ambrosio' tunnel:
- Total length: 1821 meters
- Maximum gradient: 5%
- Tunneling with traditional methods
'D'Ambrosio' and 'Leone' tunnels
Detailed design and construction documents with site assistance during the building of the underground structures between km 6.199 and the end of the lot: two tunnels with an overall length of about 6 km.
This project is part of a larger plan to build a link road between the Salerno-Reggio Calabria motorway (2nd lot) and the 'Isca Pantanelle' industrial area and SS 19-ter main national road, near the town of Polla.
Since the tunnels mainly cross limestone and dolomitic limestone with good or fair geomechanical characteristics, no particular difficulties have been encountered, except for two particular stretches at the southern entrances of both tunnels.
At the southern entrance of the D'Ambrosio tunnel, the route approaches a very steep slope with a very low angle of attack; in this situation, a conventional trench would have required excavations protected by riveting and shot concrete approx. 30m high, to be dug in a hardly accessible place.
At the south entrance of the Leone tunnel, it was necessary to pass under a private house with less than 10m overburden; for this stretch, an extensive land monitoring system has been implemented in order to monitor surface subsidence.