Stockholm Bypass Akalla Tunnel

Improving transport connectivity around Stockholm

The Akalla Tunnel forms part of the Stockholm Bypass, a major infrastructure project designed to improve traffic flow and strengthen transport connections around the western part of Stockholm.

The tunnel was excavated using conventional drilling and blasting methods and consists of two parallel tubes, each extending for approximately 1,250 metres. With excavation cross-sections of up to 280 square metres and an overburden of less than thirty metres, the project required precise planning and execution in a densely populated urban environment.

The tunnelling works were carried out in the typically stable Scandinavian granite. A particular challenge was the implementation of extensive grouting measures to ensure effective rock sealing and groundwater control alongside the ongoing excavation works.

Scope of Work

• Excavation of two parallel tunnel tubes using drilling and blasting methods
• Construction of tunnels with cross-sections of up to 280 m³
• Tunnelling works over a length of approximately 1.250 m
• Excavation under low overburden conditions of less than 30 m
• Rock sealing through comprehensive grouting measures
• Associated civil engineering and tunnelling works