TBM Olga, which is boring the east main tunnel for the H53 Pfons-Brenner lot, has officially reached 4km on the 7.6km drive.
The achievement follows progress on the west main tunnel, where TBM Wilma reached the 5km point on the 7.4km drive last month.
ARGE H53 BBT, the Porr/Marti consortium responsible for the H53 Pfons-Brenner lot, launched the two 10.37m-diameter double shield TBMs in September 2024.
Once the TBMs make their final breakthrough it will mark the end of the mechanised excavation work for the Pfons-Brenner construction site – and for the entire project as Wilma and Olga are the last two TBMs in operation for the Brenner Base Tunnel.
