The railway tunnel linking Arna and Bergen is a key infrastructure in Norway’s rail transport system. Its construction has revolutionised connectivity between the cities of Arna and Bergen, offering an efficient and fast alternative to road transport. The contract covered the construction of the track superstructure to allow a speed of 160 km/h, with the following characteristics: The project included refurbishment and modernisation works at Arna station and the new Ulriken tunnel, which is 7.7 km long, thus doubling the line on this section together with the existing tunnel. The track consists of a single-track concrete slab. In addition, 3.1 km of track on ballast was built in the tunnel itself and at Arna station, as well as at the connection to Fløen. Ballastless track system In the new Ulriken tunnel, a concrete slab track with a length of 6,825 m was installed, using Rheda 2000 sleepers and, in some locations, the Mass-Spring system. Catenary System Partial demolition and reconstruction of the catenary was carried out, including approximately 10 km of new installations, using the 20 system with 20A at the Arna station and 20C in the new tunnel. The system complies with interoperability, tunnel safety and worksite signalling regulations. Low voltage system A new low-voltage system (< 400 V) was installed in the Ulriken tunnel, which includes spot heating and lighting, emergency lighting in the tunnel and emergency power supply for critical systems such as signalling, telecommunications and emergency lighting, as well as power supply for fire ventilation and electrical installations in the high-voltage transformer substations. High voltage system A high-voltage system (11 kV) including transformer stations and high-voltage cables was installed. Telecommunications New systems were implemented for the train radio system (GSM-R), the emergency communication network (TETRA), mobile telephony and internet (MIT) and data transmission (NGN), as well as the installation of fibre optic cables at all emergency crossings and in the technical building in Fløen. Arna-Bergen Railway, Section: Arna–Fløen
Description of the works
Relevant figures
Related projects
7.7 km
LENGTH
6.9 km
SLAB TRACK
3.1 km
TRACK ON BALLAST
160 km/h
SPEED
€58.1 M
Budget
Norway
Location
Construction
Contract type
Bane NOR
Client
2019-2023
Execution period
6,940 m
concrete slab track installation.
45,100 m
of track installation on ballast.
21
switch units installed on ballast.
18.150 m³
of ballast.
18,544 m
of catenary in tunnels and stations.
9,300 m
m of 24 kV cable installed.
12
transformers.
10
substations.
13
ventilators installed in the tunnel.
49.400 m
of permanent lighting, including 128,409 m of cabling.
