Bane NOR signs further Vestfold tunnel contract

25 October 2019

Norway - A 10.8km-long double track tunnel between Drammen and Kobbervikdalen is set to be built on the Vestfoldbanen railway in Norway. Bane NOR has signed a contract with Veidekke Entreprenør for the construction of this rock tunnel.

The Drammen-Kobbervikdalen project is part of the InterCity development in Eastern Norway, and it plays an important role in building continuous double track between Oslo and Tønsberg, which is scheduled to open in 2024.

The rock tunnel itself will be a single tube double track tunnel, with a cross section of 123sqm. Once built, it will have a free space area of approximately 93m2. The tunnel will be excavated by drill and blast.

The tunnel will be driven from the tunnel portal at the Gulliksrud end as well as from two cross tunnels with cross sections of 60sqm. Two evacuation tunnels with cross sections of 25sqm will be built.

The tunnel has to be built through the Strømsåsen hill with rock consisting of granite, rhomb porphyry and hornfels. The depth of cover is up to 230m.

The tunnel will be sealed using systematic pre-injection to secure water balance in the area and safeguard the environment. The tunnel will be stabilised with bolts, sprayed concrete for a projected service life of 100 years. Water and frost protection will be achieved using a membrane covered with contact-cast vault construction.

Stine Undrum, EVP Bane NOR Infrastructure Construction Division said, “The Drammen–Tønsberg double track will allow two trains per hour in each direction between Oslo and Tønsberg, more than doubling the capacity and providing improved and more efficient transit for passengers on the Vestfoldbanen railway.”