Tunnel Boring Machine Olga in main tunnel east
@ BBT SE
The start-up ceremony on September 18, 2024, marked a significant milestone in the construction of this international infrastructure project. The event symbolically celebrated the start of tunnel excavation as the high-performance boring machines broke through the first meters of rock. Representatives of the involved companies and politicians honored the technical achievement and the progress of the project, which plays a pivotal role in the transport connection between Austria and Italy.
In H53 construction lot, double-shield tunnel boring machines (TBMs) are installed in the two main tunnel tubes heading towards Innsbruck. These machines will excavate and line approximately 15 kilometers of tunnel.
They combine the principles of gripper and single-shield TBMs. Equipped with two lateral grippers, the machines brace against the tunnel walls to transfer thrust forces while simultaneously installing segmental lining elements, which provide support for forward movement. The rotating drill head, fitted with cutting discs capable of exerting up to 32 tons of pressure per disc, presses against the rock. The rolling motion of the discs fractures rock fragments from the rockface. Water jets cool the cutting tools and minimize dust formation during operation. The excavated material is collected by scrapers at the drill head and transported through channels to the center of the machine, where it is transferred onto a conveyor belt via a hopper. The material is then carried out of the tunnel and deposited at the Padastertal muck disposal site.
