Danviksbro
Encyclopedia
Bascule bridge
A bascule bridge is a moveable bridge with a counterweight that continuously balances the span, or "leaf," throughout the entire upward swing in providing clearance for boat traffic....
in central Stockholm
Stockholm
Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...
, Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
, connecting the eastern end of Södermalm
Södermalm
Södermalm, often shortened to "Söder", is a district in central Stockholm. It covers the large island formerly called "Åsön". With a population of 99,685, it is one of the most densely populated districts of Scandinavia...
to the eastern municipality Nacka
Nacka
Nacka is the municipal seat of Nacka Municipality and part of Stockholm urban area in Sweden. The municipality's name harks back to an 16th century industrial operation established by the Crown at Nacka farmstead where conditions for water mills are good...
. Under the bridge, the canal Hammarbykanalen carries the water of Hammarby Sjö
Hammarby Sjö
Hammarby Sjö is a watercourse in central Stockholm, Sweden. Separating Stockholm City Centre from South Stockholm, or, more locally, Norra Hammarbyhamnen on eastern Södermalm from Södra Hammarbyhamnen, it connects Saltsjön to Årstasjön.Covering a surface of 34 hectare and having an average depth...
over to Saltsjön
Saltsjön
Saltsjön is a bay of the Baltic Sea that extends from Stockholm archipelago to the inner city of Stockholm. Its innermost part reaches the eastern shore of Gamla stan at Skeppsbrokajen. It is navigable for large craft and the major ferry lines to and from Stockholm pass through it...
. The bridge, actually two separate bridges carries the railway Saltsjöbanan
Saltsjöbanan
Saltsjöbanan is a suburban rail system between Stockholm and Saltsjöbaden in Nacka, Sweden. It is in length and has eighteen stations in use. An average of 19,600 journeys are made on an ordinary workday. The line is mainly single track, and is isolated from Sweden's national railway network,...
and a road.
For unknown reasons the location of the bridge, like many other places along the shores of Sweden and Norway, was named 'Danviken', meaning danernas vik, "The Bay of the Danes", and until the early 20th century most people called it Dannviken (short a, like Danmark is still pronounced) rather than, like is common today, Daanviken (long a).
History
Since King Gustav VasaGustav I of Sweden
Gustav I of Sweden, born Gustav Eriksson of the Vasa noble family and later known simply as Gustav Vasa , was King of Sweden from 1523 until his death....
(1496–1560) had the water level of the lake Hammarbysjön increased by 4.8 metres, the lake emptied into Saltsjön through a small rivulet overshadowed by a simple wooden bridge and the familiar silhouette of an old mill, and for many centuries Danviken remained mostly renowned for its hospital, Danviks hospital
Danviken Hospital
Danvikens hospital was a historical Swedish hospital, Insane Asylum and Retirement home in Stockholm, active in 1558-1861. The area belonged to Stockholms kommun until 1984, when it was transferred to Nacka kommun....
, which the king had moved from Riddarholmen
Riddarholmen
Riddarholmen is a small islet in central Stockholm, Sweden. The island forms part of Gamla Stan, the old town, and houses a number of private palaces dating from the 17th century...
near the city.
In 1922, a railway viaduct built in 1893 was demolished together with the old bridge, both replaced by a single leaf bascule bridge
Bascule bridge
A bascule bridge is a moveable bridge with a counterweight that continuously balances the span, or "leaf," throughout the entire upward swing in providing clearance for boat traffic....
with its concrete counterweight hanging over the 14 metres wide roadway shared by trains and vehicles. On the eastern side of the canal a concrete viaduct connected to the bridge, and the bridge's load-carrying steel truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...
es left a horizontal clearance of 12,5 metres for the ships below.
To deal with increasing post-WW2 traffic loads, the capacity of the bridge was increased in 1956 by adding a new bridge south of and parallel to the old, the two structures separated by less than a metre. The new bridge was 22,2 metres wide, of which 14 metres were used by vehicles, and 5 metres for bicycles and pedestrians, which effectively left the trains and bicyclists have the old bridge for themselves. A single leaf bascule bridge was chosen this time to, but this time having in mind that the canal was prospected to be widened, which would hopefully be done easily by adding more bridge to the present unaltered structure.
By the 1970s traffic had increased enough again to motivate a redevelopment of the traffic system surrounding the bridge and the enlargement of the bridge itself. This was simply done 1973-1977 by replacing one of the open web girders for a steel girder underlying the deck, thus giving space for additional cantilevering roadways.
Plans
There are plans to a new high double track tramway bridge, carrying the SaltsjöbananSaltsjöbanan
Saltsjöbanan is a suburban rail system between Stockholm and Saltsjöbaden in Nacka, Sweden. It is in length and has eighteen stations in use. An average of 19,600 journeys are made on an ordinary workday. The line is mainly single track, and is isolated from Sweden's national railway network,...
, which will be redefined from railway to tramway. Rising cost estimates (now about 3 bn SEK) have delayed the construction start, which is now planned to be around 2012.
External links
- webbkameror.se - Webcam at Danviksbron
- Stockholmskällan - Historical images of Danviksbron.