ABSTRACT
At the Follo Line project, four hard-rock double-shield TBMs have been operating from one single access-point, excavating in total 36 km of tunnels. This paper will describe the requirements for the machines and the results of the excavation, including performance in “extreme hard-rock conditions”, in combination with continuous mapping of the geology and the performance of grouting in areas with water leakages. Other main activities, such as production of lining and depositing of excavated material, are performed within the rig area. The deposit of the excavated material is performed in accordance with specific procedures, with the intention of reusing it as a foundation for a future residential area. The paper will also address the challenges with structural noise and disturbances to neighbors during the construction of the tunnels.
