Breakthrough was achieved on 6 June on the 1,250m long Hjälta Tunnel, the second tunnel to be constructed on the Botnia rail line in the north of Sweden.
Being undertaken for client, Botniabanan AB by AF Spesialprosjekt, work on the tunnel began in August 2000 and is scheduled to be complete in February 2002.
The tunnel has been constructed by drill and blast with rock reinforcement progressing in parallel with the excavation work.
An access tunnel was driven down to the line of the tunnel at the half way point. This provided two extra working faces, enabling better use of resources and a shorter construction time. The access tunnel will act as a service/rescue tunnel when the railway is in operation.
