SCANDINAVIA'S STUNNING SPAN

The owner and contractors on the record-setting 16.4-km bridge-tunnel between Malmo, Sweden and Copenhagen, Denmark are using extensive prefabrication and open contracts to overcome some major setbacks and finish Scandinavia's first direct road and rail link to continental Europe on time and close to budget. Planned to minimize obstructions of water flows between the North and Baltic Seas, the link includes a 4-km tunnel from the Danish coast to a 4.1-km artificial island at midcrossing. The island allows the road to rise above twin railroad tracks on a viaduct onto the 7.9-km double-deck bridge, which includes a 1.1-km-long cable-stayed section with a 490-m main span. Built in up to 8 m of water, the bridge is founded on caissons sunk to bedrock to an average depth of 18 m below water. Most spans are 140 m long, dropping to 120 m in places. Deck girders are approximately 10.5-m-deep with a 25-m-wide concrete road built compositely over twin steel trusses on either side of the railroad. Zig-zagging diagonals of the trusses connect with their bottom girders every 20 m, coinciding with crossbeams. The 8.6-m-deep rectangular tunnel is prefabricated in 22-m segments and contains four parallel galleries for tracks and roads, plus a conduit for access and services. To avoid ground settlement damage, each 175-m-long element is designed as eight separate elements stressed together temporarily.