The project concerns the national road 106 Jonica between km 49+485 and km 51+750. The project layout has a lenght of about 2,300 km.
In this section 4 tunnels are located (Palizzi L = 450 m, Ambusena L = 135 m, Peristeri L = 1,000 m e S.Antonino L = 700 m) and n. 2 viaducts (Fiumara e Simmero).
SOIL Srl is in charge of the detailed design for construction and of the technical assistance during works of all the above tunnels From the geological and geomechanical point of view, they are is located in claystones and methamorphic rocks .
All tunnels were excavated using a preliminary lining composed of steel ribs and of a layer of fiber reinforced shotcrete; tunnel invert arch and final concrete lining were casted at short distance from the face, depending on monitoring data. In the clayey segments, a pre-confinement intervention was carried both at core and around the future excavation using fiber-glass tubes injected with grout.