The Guldborgsund Tunnel is an Immersed Tunnel connecting the islands of Lolland and Falster in southern Denmark. The tunnel was built between 1985-1988 and consists of two tubes, each carrying two lanes of highway traffic.
The immersed tunnel is constructed of two 230 m long tunnel elements that are cast together in the middle forming one monolithic structure of 460 m. Due to differential settlements between the portal structure and the immersed tunnel itself, the Omega Seal in either end of the tunnel have been exposed to large shear forces. In order to ensure the water tightness, Ramboll has design a secondary construction between the tunnel and the portal accommodating a second Omega Seal. Due to the size of the monolith and potential for continued settlement the new omega joint has been designed to accommodate rather large movements.
The project includes a number of complexities;
- Ensuring water tightness of the console cast onto the existing structure.
- Fixation of the new Omega Seal.
- Altering the geometry of the portal structure around the existing Omega Seal.
Ramboll was engaged to develop the detailed design and tender documentation for the new watertight joint followed by site supervision.