The extension of the Bologna - Conca d'Oro line serves the north-west area of the city and will allow connecting the area to the city centre, line A and the Termini railway station.
The project consists in the construction of civil works, reinforcements and systems, all of which underground, running about 1,100 metres in a double-track tunnel, as well as in the construction of a station and two ventilation shafts. Advanced technologies were used, including the excavation of a large diameter double-track tunnel using EPB technology with chemical/cement injections and jet grouting for the “bottom plugs”, as well as the compensation grouting technique. The contract also includes 3 underground car parks serving the stations of Annibaliano, Conca d’Oro and Jonio, of which the latter only will be provided with technological systems, while the other two will be left roughcast.
The use of an EPB (Earth Pressure Balance) TBM (Tunnel Boring Machine) allowed excavating a tunnel below the water table at pressures reaching 2/2.5 atm.
|MAIN TECHNICAL DATA:|
|Line tunnel length: 950 m (twin rail)|
|Internal diameter of the tunnel: 8.65 m|
|Excavations: 386,000 m³|
|Concrete: 172,000 m³|
|Steel for concrete: 22,000 t|
|Reinforced concrete slurry walls: 23,000 m2|
|Jet-grouting: 178,000 m|
|Compensation grouting: 2,000 m3|
|Railway construction: 2,200 m|
Rome Metro System, Line B1 – Conca d’Oro/Jonio