Completed in 2005, the MAC-LRT Stations & Tunnels – Twin 21′ Diameter Tunnels under Minneapolis Airport and Runways for Light Rail Station project consisted of constructing two 1.8 miles long and 85 feet at the deepest point, 21-foot diameter EPB tunnels under the Minneapolis-St. Paul International Airport, which required careful precautions regarding the risk of ground settlement and airport disruption. The project features one of the largest machine-bored tunnels in North America, and a 2,520 square foot station at Lindbergh Terminal. The project team used earth pressure balanced tunnel boring to mine the two tunnels and station area 65 feet beneath the nations 8th most active airport. The result is a new primary transportation link between downtown Minneapolis, the airport and the Mall of America. Formidable subsurface challenges, concerns for water infiltration and aviation related restrictions led to the selection of the bored precast concrete tunnel lining system. Each tunnel ring was constructed with seven bolted precast concrete segments with compression gaskets ensuring watertight connections as a back grouting operation maintained continues ground support.
Project Details
- Owner: Metropolitan Airport Commission
- Location: Minneapolis, Minnesota, United States
- Performed as: Johnson Bros. Corporation
- Project value: $34,688,953.00
- Completion Date: February 2005