Tunnelling for the Turin Median Collector has reached its first intermediate milestone.
One year after being launched from Arrivore Park, TBM Gaia has completed 2.7km of tunnelling to arrive at service shaft PZ030, near Turin’s Monumental Cemetery.
Tunnelling is being delivered by Colmeto Scarl, a consortium of Itinera (51%) and Ghella (49%).
The new collector will be 14km, with 9.5km of tunnel excavated by TBM. Tunnelling is being carried out in heterogeneous ground conditions at a depth of approximately 20m and more than 10m below the groundwater table.
TBM Gaia is a hydroshield machine with a 4.08m diameter diameter. It is advancing at an average speed of approximately 3cm per minute.
During the first 2.7km of excavation, the team encountered particularly complex geological conditions, with heterogeneous and highly abrasive materials. To date, these conditions have required more than 80 hyperbaric interventions for maintenance of the cutterhead, with operations carried out at a working pressure of 1.5 bar.
The Median Collector will serve the city of Turin and 20 municipalities in the metropolitan area to the south and west of the Piedmont regional capital.
