Projects: Underground engineering
'Caramanico Terme' main national road
Main features of the designed tunnels:
- "Caramanico" tunnel: 486 meters long
- "Fontegrande" tunnel: 1451 meters long
- Natural tunnels with traditional excavation
- Internal diameter: 10.10 meters
- Monitoring during construction phase
Design of the Caramanico and Fontegrande tunnels
The 1989 landslide which cut the inhabitants of Caramanico Terme and S. Eufemia a Maiella off spurred ANAS 'Autonomous Italian Road Body' (Pescara district) to start up an important and conclusive road restoration operation entailing the building of two tunnels: the Caramanico (486 meters long) and the Fontegrande (1451 meters long). Both are two-lane road tunnels with an internal diameter of 10.10 meters.
Drawing up the shop drawings, which had to compensate for an unsatisfactory final design as concerned geotechnical problems, involved carrying out an in-depth geological investigation. It also regarded:
- determining the static and technological dimensions of the natural tunnels to be dug with traditional mechanical means through detrital covering material from gravitational sliding (maximum ground cover of 70 meters - Fontegrande and 40 meters - Caramanico);
- the building of the Caramanico tunnel in particular which involved passing under the town of the same name, with very little ground cover in some places; this unavoidably led to problems with the foundations of buildings along the path, which were brilliantly solved during the work;
- the static design of the mouths and artificial tunnels.
Careful and accurate monitoring measurements were carried out during all building stages, which also allowed the most critical steps to be kept under control. Today both tunnels have been successfully completed without damaging either buildings or structures.