The East Bridge
The 6.8 km road bridge between Zealand and Sprogø is part of the Storebælt Bridge and, with its main span of 1,624m, is the world’s second longest suspension bridge.
At its highest point, the road deck is 75m above sea level, which is why wind conditions have a major impact on traffic on the bridge. The gradient of the bridge is a maximum of 2.1 per cent, i.e. somewhat less than the highest gradients of other Danish motorway sections, which rise up to 3.5 per cent.
The East Bridge’s bridge deck is made of steel while the two pylons, two anchor blocks and 19 bridge piers are made from reinforced concrete.
The concrete sub-structure comprises pylons and anchor blocks as well as bridge piers and abutments. The steel superstructure comprises spans and cables.
The suspension bridge between the two anchor blocks is around 2,700m long. It is made up of the free span between the two pylons of 1,624m plus the two side spans between the pylons and anchor blocks of 535m each.
The East Bridge spans Storebælt’s Eastern Channel, an international waterway with a depth of approximately 60m. Every year, around 25,000 ships pass under the Storebælt bridges. Approximately 95 per cent pass under the East Bridge, which has a navigational clearance of 65m. The East Bridge’s large, free span was determined by means of extensive manoeuvre simulations for maritime traffic and helps to ensure minimum risk of collision.
The pylons, anchor blocks and bridge piers nearest the passage span have been constructed so that any collision would not cause critical damage to the bridge. As an extra safety precaution, a system that monitors shipping in the Storebælt has been set up. The system helps to ensure that all large vessels sail though the Eastern Channel.
The West Bridge
The West Bridge is a 6.6 km long, combined road and rail bridge resting on 63 bridge piers and two abutments. Both the super and sub-structures are made of reinforced concrete. The West Bridge curves horizontally with a radius of 20 km. Chosen for both aesthetic and safety reasons, this gives drivers a varied experience during their crossing of the West Bridge.
Due to the limited navigational clearance of 18m, shipping in the Western Channel is restricted to vessels of max. 1,000 GRT (Gross Register Tonnage).
The two passage spans for north and south bound shipping are marked with double leading lights and red/green buoyage (beacons and lights). In addition, the navigation spans are equipped with automatic fog detectors and foghorns. There is 260m between the north and south bound navigation channels.
To further enhance safety, a system has been set up to monitor shipping in Storebælt. This helps to prevent large vessels accidentally sailing through the Western Channel instead of the Eastern Channel.
Milestones in the history of the Storebælt Fixed Link
- 10 June 1987: The Danish parliament adopts the Construction Act for the Storebælt fixed link.
- 30 August 1990: The boring machine Selandia begins the boring of the southern tunnel tube.
- 12 April 1991: The floating crane, Svanen, places the first West Bridge caisson off Knudshoved.
- 14 October 1991: The two tunnel tubes from the Sprogø side are flooded due to water penetrating through the seabed at the front of the boring machine, Jutlandia.
- October-November 1992: The world’s largest underwater groundwater lowering starts. The MOSES project removes some of the pressure in the subsoil to facilitate the work of the tunnel boring machines.
- 21 April 1993: The first caisson for one of the East Bridge’s pylons is sailed from Kalundborg and immersed on the bottom of Storebælt.
- 15 October 1994: Prince Joachim is the first human through the tunnel.
- 14 June 1998: Queen Margrethe II opens the Storebælt fixed link.