By rosebell
The joint venture was appointed by ÖBB Infrastruktur to equip the twin-bore railway tunnel with telecommunications, high-voltage power systems, distribution boards, lighting, escape route signage and mechanical systems for air conditioning, ventilation and firefighting water.
55km of Slab Track to Be Installed
The fit-out includes approximately 55km of slab track, connections to ballasted track, noise protection, substructure and steelwork, earthworks, concrete and ceiling works, as well as turnouts and ballasted track at the eastern and western portals.
Work is currently concentrated on the Styrian side. From mid-2027, activities will increasingly shift towards the Gloggnitz portal in Lower Austria.
The installation programme includes approximately 1,000km of cables, more than 3,200 lights, 55km of illuminated handrail, around 13,500 signs and 10,600 track support slabs, each measuring 5m in length.
Siemens Supplies Tunnel Control Systems
Siemens is supplying the control and telecontrol systems, automation and protection technology for the Semmering Base Tunnel.
A total of 69 SICAM A8000 control-system cabinets will provide centralised and decentralised control of the tunnel’s technical systems. The system automates 56 cross-passages and integrates approximately 25,000 hardware signals.
The control infrastructure will coordinate systems including power supply and ventilation, allowing tunnel equipment to be monitored and controlled efficiently.
The project also includes 24kV blueGIS switchgear, described as the first F-gas-free switchgear installed in an Austrian tunnel. Combined with SIPROTEC 5 protection relays and supervisory computers, the system enables continuous monitoring and early fault detection across the tunnel’s electrical infrastructure.
Semmering Base Tunnel to Open in 2029
The 27.3km twin-bore Semmering Base Tunnel will connect Gloggnitz in Lower Austria with Mürzzuschlag in Styria, providing a lower-gradient railway route across the Semmering region.
Once operational, trains will be able to travel through the tunnel at speeds of up to 230km/h, reducing journey times by around 30 minutes. The tunnel will also improve freight capacity along the strategically important Baltic–Adriatic European rail corridor.
Together with the Koralm Railway, the Semmering Base Tunnel will create a lower-gradient route on Austria’s Vienna–Villach Southern Railway. This will allow heavy freight trains to operate without requiring two locomotives on the steep sections of the existing route.
