Monitoring the track on the Dovre Line

The latest instrumentation was installed in November. They show with millimetre precision any deviations on the train track through Stange town centre.

- It's a peace of mind during the work on the new double track," says Jørgen Sandvoll, Site Manager at Gjermundshaug Anlegg.

Trains are running as normal on the Dovre Line. At the same time, a new double track is being built.

- "It's absolutely crucial that the track is monitored," says project manager Jaqueline Andersen at Bane NOR. Gjermundshaug Anlegg has been awarded the contract for the station area. There, 1.8 kilometres of new double track is being built.

Demanding challenge

- Train traffic on neighbouring tracks during the work is a demanding challenge. That's why it's crucial that tracks are continuously monitored. It's about safe train traffic and responsible development," says Andersen at Bane NOR.

The work through Stange town centre and Stange station is part of the InterCity project Kleverud-Sørli-Åkersvika, which will provide 30 kilometres of new double track through the entire municipality.

Gjermundshaug Anlegg is building the new double track with culverts, railway technical installations, noise barriers, technical buildings, new commuter car parks, platform roofs, lifts, walkways and cycle paths. The contract value is NOK 1.1 billion.

Sheet piling next to tracks

- "Now that we're working close to the tracks, instrumentation with track monitoring gives us peace of mind. It provides alarms if the limit values for the track that have been set are not maintained," says Sandvoll.

Cautus Geo monitors the track with three different SAAX wires. Alerts are set up if the limit values are shifted by more than 10 millimetres.

- We started monitoring in August. We instrumented the first part of the track with a 40 metre SAAX. Since then, we've added a 100-metre SAAX and another 130-metre SAAX along the track. These are areas where work is being done close to the track," says geologist Lars Steinar Hefre of Cautus Geo.

Historically longest

The 130 metre SAAX inclinometer is the longest continuous SAAX Cautus Geo has ever installed on railway tracks.

- There are no limitations. We can monitor very long distances. In the past, we have carried out longer installations. Then we connected shorter separate instruments and overlapped them. In Cautus Web, this is digitally processed into a coherent instrument," says Hefre.

Gjermundshaug Anlegg is laying track in the station area in two phases.

- The first part is now being carried out. When it's finished, the train will use the new track. The old track will then be demolished and we'll do the same exercise on the other side of the railway area," says Sandvold.

Work on the station area is estimated to take approximately four years.

EQUIPMENT:

• Three SAAX inclinometers (horizontally on the railway to check settlement of the track during piling, digging, pipe pressing, etc.)
• Sensors (are 40 metres, 100 metres and 130 metres).
• Data logger cabinet (for continuous transfer of data).
• Cautus Web (collects, analyses and presents data and alerts when limit values are exceeded).