Follobanen Three-track tunnel

On the right track with Concremote

The AF Group has started using Concremote on one of its projects on the Follobanen, the Three-track tunnel. This should prove to be very profitable.

Building for the future

The purpose of the development is to create an environmentally friendly and efficient transport link that makes it easier to live and work where you want, which in turn will remove some of the pressure from the expected population growth in the area surrounding Oslo in the coming years. According to ssb (Statistisk sentralbyrå), 370,000 more inhabitants are expected to be living in Oslo and Akershus by 2040.

Doka's capabilities have been very useful in the Follobanen project. Since the tendering process started in 2014, we have been involved in many of the projects on the Follobanen, including the Three-track tunnel project for the AF Group.

Advances on the construction site

Concremote has been used in the Three-track tunnel and has received very good feedback from the AF Group. Amongst others, Bernt Kristiansen, who is one of the country's most knowledgeable and experienced concrete technologists.

The purpose of Concremote is to have control over the property development, so that the formwork can be taken down as quickly as possible. A total of 21 constructions have been cast with Concremote as a tool for strength control on this project, 11 with the truck "Julie" and 10 with the truck "Lina".

When the casting work was carried out in the Three-track tunnel, three sensors were installed on the formwork trucks, two on the bottom deck and one sensor in the middle of the interior wall. Notice of attained strength was distributed to operating personnel in AF and key personnel in Bane NOR by using automatically sent SMS and/or e-mail.

One week saved

Taking down the framework as soon as possible provides a time and financial gain. By using Concremote in the Three-track tunnel, the AF Group has been able to start taking down the framework when the supervisor in charge has received a notice of attained strength, at any time of day. The AF Group's estimate is that if they were to use traditional sampling to determine whether the desired strength was achieved, they could start removing the framework almost six hours later than when using Concremote.

This gives a savings of 21x6 hours = 5.25 days. In summary, the AF Group assume that total time savings for the Three-track tunnel represents one week's progress. This in turn results in a one week shorter rental of formwork materials, machinery and saved manpower time.

Concremote

Doka's system for controlling the concrete's strength development in the concrete when measuring temperature development. The maturity development of the various concrete mixes is calibrated by casting cubes and storing them in Doka's proprietary insulated crates. Pressure strength is measured at various times and calculation models for the concrete prescriptions are prepared.