Brenner project marks progress milestones 03 Aug 2017

Herrenknecht TBM ready for Mules 2-3 Lot drive

The Salini-Impregilo/Strabag JV has recorded two milestones for the drill+blast and TBM excavations for its Tulfes-Pfons Lot at the north end of the Brenner Base Tunnel project under the Alps between Austria and Italy.

The JV has completed principal drill+blast excavations near Innsbruck on the Tulfes-Pfons Lot and reached the halfway milestone on the 15km long TBM drive for the exploratory tunnel. By 1 August the JV had excavated a total of 30km by TBM and drill+blast since excavations began in mid-2014. The last main milestone for the contract is completion of the Herrenknecht TBM exploratory tunnel drive, which is expected by Spring 2019.

TBM will excavate the Mules 2-3 exploratory tunnel

Access to the Isarco River underpass drives

Elsewhere on the project, the Astaldi/Ghella-led JV is working on the Mules 2-3 Lot, where initial drill+blast works are progressing and a Herrenknecht TBM is due to launch later this year on the exploratory tunnel section. The works include nearly 40km of main running tunnels, the TBM exploratory tunnel of almost 15km and about 10km of additional tunnels.

In Italy, the Salini Impregilo/Strabag/Collini Lavori/Consorzio Integra has started drill+blast work on the challenging underpass of the Isarco River using ground freezing to control water ingress under the river and jet grouting to stabilise the predominantly soft ground geology along the 5.8km length of the twin tube running tunnels as they approach the junction with existing rail infrastructure.

In the meantime, the project delivery client BBT-SE told TunnelTalk that bid assessment continues for the final main tunnelling contract for the Pfons-Brenner Lot, which involves about 50km of main running tunnel excavation. Five consortia have presented bids:

• Strabag/Salini-Impregilo
• Pizzarotti, Implenia Osterreich, Metrostav, BeMo Tunnelling
• Acciona Construccion and CMC di Ravenna
• Porr Bau, Hinteregger, Condotte and Itinera
• Astaldi, Ghella, Oberosler Cav Pietro, PAC