Hølendalen Bridge

Hølendalen Bridge Hølendalen bru
Coordinates	59°32′13″N 10°43′37″E / 59.537°N 10.727°E / 59.537; 10.727Coordinates: 59°32′13″N 10°43′37″E / 59.537°N 10.727°E / 59.537; 10.727
Carries	Østfold Line European Road E6
Crosses	Hølendalen, Såna
Locale	Hølen, Vestby, Norway
Owner	Norwegian National Rail Administration Norwegian Public Roads Administration
Characteristics
Design	Cantilever
Material	Concrete
Total length	416 m (1,365 ft)
Height	50 m (160 ft)
Longest span	128 m (420 ft)
No. of spans	4
History
Architect	Lunde og Løvset
Engineering design by	Johs Holt
Constructed by	Skanska
Construction cost	174 million kr
Opened	21 September 1996 (1996-09-21)
Replaces	Hølen Viaduct
Hølendalen Bridge Location in Akershus

The Hølendalen Bridges (Norwegian: Hølendalen broer) are three parallel concrete cantilever bridge which cross Hølendalen in Vestby, Norway. One carries two tracks of the Østfold Line, the other two carry four lanes of European Road E6. The bridges have four spans, the two in center at 128 meters (420 ft) and the two outer at 80 meters (260 ft). The overall lengths are 416 meters (1,365 ft). The bridges are up to 50 meters (160 ft) above the valley and the creek of Såna.

Proposals for bridges were first made in 1988, as part of a joint planning of a new high-speed railway and freeway through Vestby. Johs Holt were the structural engineers and Lunde og Løvset architects. The railway bridge was built first and opened on 21 September 1996. The freeway bridges followed afterwards. They have won among other awards Betongtavlen in 1999.

There are three bridges which cross Hølendalen. The eastern-most carries two tracks of the Østfold Line. Its northern end is situated 46.02 kilometers (28.60 mi) from Oslo Central Station. The line is electrified and is dimensioned for speeds up to 200 km/h (120 mph). The two western bridges carry a combined four freeway lanes of European Road E6. At the southern end both the railway and freeway enter respective tunnels. This is the 910-meter (2,990 ft) Stavengåsen Tunnel for the railway and the twin-tubed Follo Tunnel for the freeway.

The three concrete cantilever bridges have the same span and length dimensions, with pillars located at the same relative points. This allows for a cleaner visual appearance. The overall length is 416 meters (1,365 ft). The two central spans each measure 128 meters (420 ft), while the inner spans measure 80 meters (260 ft). At the highest the bridges are 50 meters (160 ft) above the valley floor. Each span was anchored at each end in a twin concrete pillar. These were 4.47 meters (14.7 ft) wide. The depth started at 1.8 meters (5 ft 11 in) at the foot and decreased to a minimum of 1.0 meter (3 ft 3 in) on the tallest pillars. There is a 3.0-meter (9.8 ft) gap between the twin pillars. All pillars are fastened into bedrock through a deep foundation. For the middle pillars with involved piling down up to 28 meters (92 ft).