Keller wins global projects award for work on the Follo Line Project in Norway Sponsored

Keller's work on the prestigious Follo Line Project in Norway has won an Award of Merit in the Rail category at the ENR (Engineering News-Record) Global Best Projects competition. The annual contest honours construction and design excellence from the past year around the world and is organized by ENR, a prestigious American construction magazine, and judged by an independent panel of industry professionals. Representatives from Keller's Follo Line team picked up the award at a ceremony in New York City on October 2.

The Follo Line is currently the largest infrastructure project in Norway. Connecting the capital, Oslo, with the suburban town of Ski, it includes a 20km-long twin-tube tunnel; the longest railway tunnel in the Nordic countries. A complex project which demonstrated Keller collaboration and expertise at its best, Follo Line saw three different business units (and nearly 70 employees) work together to implement numerous ground engineering techniques, including soil stabilization by jet grouting and deep soil mixing, ground anchors, micropiles and injection works. At the workplace, there were many different technologies and nationalities, so logistics and planning were important.

Keller installed 1000 pieces (17,600m) of Ø800mm and more than 5000 pieces (67,500m) of Ø1200 mm jet grouted columns using the single jet system with variable parameters to reach the design diameter up to 22m deep, working day and night shifts next to active railway lines in order to deliver on time. Special filter presses were installed for treating the backflow, minimizing the environmental footprint. The work was accompanied by real-time monitoring of deformations by hydraulic load cells. Keller's work began in May 2016 and in July 2019 the last jet grouted column was completed on-site (pictured above).

"We developed a new way of installing pre-stressed strand anchors," said Dominik Gächter, Branch Manager, Norway. "I would like to thank the whole team on site for their commitment to making this project a success for Keller. I would also like to thank the project team from Bane NOR for the excellent co-operation and trust in Keller over the last three years. Hopefully, we can support Bane NOR on other projects in Norway with our various geotechnical solutions in the future."