The Great Belt Link, the East Bridge, Denmark

Photo: JacobBentzen
The completed bridge.
This high-level motorway bridge is one of the three major components in the USD 3.5 billion Great Belt Link.

Being the landmark of the link, the East Bridge spans the international shipping route between the Baltic Sea and the North Sea, allowing a clearance of 65 metres below the bridge girder. The bridge carries a dual-lane motorway with emergency lanes.

With a main span of 1,624 metres the East Bridge has the second longest suspended span in the world. The side spans are 535 metres each and the approach bridges are 2,544 metres and 1,552 metres long, respectively. The sub-structures including pylons are made of concrete and the superstructure of steel.

Superstructure

The superstructure is an aerodynamically shaped fully welded closed box girder, and is continuous over the full length of 2,694 metres between the two anchor blocks.

The traditional expansion joints at the tower positions are thus avoided. In addition, hydraulic buffers between the anchor blocks and the girder are installed to restrain longitudinal short term movements.

Compared to a traditional system with joints at the pylons, the continuous system in combination with the hyrdraulic buffers improves the overall stiffness and stability of the bridge and leads to low maintenance costs.

Box girder

The box girder is suitable for rationalised repetitive fabrication. The interior surfaces, which comprise about 80% of the total steel surface, are unpainted and are protected by dehumidification of the inside air volume.

Cables

The length of the main cables is approximately 3,000 metres with an outer diameter of 0.82 metres. The cables were ínstalled by aerial spinning.

Pylons

Rising 254 metres above sea level, the pylon has slightly tapered legs with a rectangular, hollow cross-section. The lower part around the water line is designed as a monolithic structure with heavily reinforced 1.2 metres thick walls to resist impact loads of 670 MN from a 250,000 DWT tanker.

The pylons are supported by large foundation caissons placed on a small gravel bed at a water depth of approximately 20 metres. The cellular 78x35 metre caissons, 20 metres high and weighing 30,000 tonnes, were cast in a dry dock and towed 30 nautical miles to the bridge site.

Anchor blocks

Located at a water depth of approximately 10 metres, the anchor blocks shall resist cable forces in excess of 600 MN.

Excavation to 25 metres below sea level was necessary to construct a wedge-shaped foundation base suitabe for large horizontal loading.

Each anchor block caisson covers 6,100 m2 and weighs 50,000 tonnes in the transportation stage from the dry dock.

LAST UPDATED: 01.04.2017