Skaugum Tunnel
Double | |
Track gauge | 1,435 mm (4 ft 8+1⁄2 in) |
---|---|
Electrified | 15 kV 16.7 Hz AC |
Operating speed | 160 km/h (99 mph) |
The Skaugum Tunnel (
Specifications
The Skaugum Tunnel is a 3,790-meter (12,434 ft)
History
The Asker Line runs from
Work on geological surveys in the area started prior to 2001, with surveys being performed by the Geological Survey of Norway.[3] The contract to build the tunnel and all other earthwork on the section from Solstad to Hønsveien was awarded to Mika, with the tunneling costing NOK 425 million.[11] The tunnel was built using the drilling and blasting method using two points of entry, the entrance on the Asker side and from a crosscut at Skaugum.[2] Work started in February 2002 and was concluded in May 2005. Construction involved blasting 450,000 cubic meters (16,000,000 cu ft) of earthwork and drilling 275 kilometers (171 mi) of holes for pre-injection. The construction used 14,000 cubic meters (490,000 cu ft) of gunite, 14,000 cubic meters (490,000 cu ft) of concrete, 24,000 bolts, 35,000 cubic meters (1,200,000 cu ft) of water- and frost protection, 25,000 cubic meters (880,000 cu ft) of noise- and frost isolation and 9.4 kilometers (5.8 mi) of cable conduit.[12] Near the entrance at Asker, the tunnel is closest to the surface, and is between 2 and 3 meters (6 ft 7 in and 9 ft 10 in) below the basements of residential houses. During the construction of this part, the construction was as slow as 8 to 10 meters (26 to 33 ft) per week, of which half the time was used for injections to choke the tunnel.[2]
During the construction there was an accident where a worker driving a
A concern from people living along the tunnel was that they would be subject to low-frequency noise. Originally the municipalities of Asker and Bærum had demanded that residents be subject to a maximum of 27 decibel A-weighting (dBA), but the National Rail Administration appealed the requirements and was permitted to allow up to 32 dBA. In March 2004, a test was done in the tunnel to insure that the requirements would be met, as low-frequency sound is difficult to predict. Measurements after the opening of the tunnel showed background noise of 30 dBA, that no-one was subject to 32 dBA or higher, and that it was nearly impossible to measure the passing of trains.[14]
Among the major concerns were leaks;[2] during the construction on the Romerike Tunnel, there was a one-year delay and severe cost overruns due to improper construction methods.[15] One of the main aims in the Skaugum Tunnel project was therefore to avoid similar leaks, and the criteria were set to 4 liters (0.88 imp gal; 1.1 U.S. gal) per minute per 100 meters (330 ft). This was achieved by using sufficient time for the pre-injection,[2] as well as continuous pregrouting through the entire tunnel.[3] However, water still dripped into the tunnel, which caused several types of damage. In some places, it dripped onto the track causing it to rust, while in other places it fell onto electrical equipment. There were also issues with water running down the walls and collecting in the cable conduit, and the limestone in the water mixing with the ballast.[7] By 2011, the emergency lighting system had to be replaced because of the high humidity. The National Rail Administration has stated that savings made by the specifications in the water and frost protection methods have caused high maintenance costs because the small leaks which are present have done a lot of harm. In addition, areas with leaks suffer from icing. This has been part of a trend where older tunnels are nearly maintenance-free, while newer tunnels have incurred high maintenance costs.[16]
Laying of tracks, signaling, power supply and other infrastructure was done by Baneservice. The cost for the entire section from Asker to Sandvika was NOK 70 million. The work was done in February and March 2005.[17] The opening of the tunnel and the rest of the section from Asker to Sandvika took place on 27 August 2005.[18]
References
- ^ a b c Norwegian National Rail Administration (2007). "Jernbanestatistikk 2007" (PDF). Archived (PDF) from the original on 24 July 2011. Retrieved 2 December 2011.
- ^ a b c d e Valmot, Odd R. (9 February 2004). "Under jorden til Asker". Teknisk Ukeblad (in Norwegian). Archived from the original on 12 November 2005. Retrieved 2 December 2011.
- ^ ISSN 1503-8181. Archived from the originalon 22 April 2012. Retrieved 2 December 2011.
- ^ Holmøy, Kristin H.; Nilsen, Bjørn (May 2004). "Site investigation results versus tunnelling conditions – a study with emphasis on water leakage based on Norwegian cases" (PDF). Norwegian University of Science and Technology. Archived (PDF) from the original on 24 April 2012. Retrieved 2 December 2011.
- ^ "Injeksjon – erfaringer fra Jong–Askertunnelen" (in Norwegian). Norwegian Public Roads Administration. 12 December 2005. p. 58. Archived from the original on 15 April 2012. Retrieved 17 May 2012.
- ^ Norwegian National Rail Administration (March 2007). "Lysaker – Sandvika Fra to til fire spor" (PDF) (in Norwegian). Archived from the original (PDF) on 27 May 2011. Retrieved 19 February 2011.
- ^ a b Olafsen, Egil. "Noen drift's erfaringer fra tunneler" (in Norwegian). Norwegian National Rail Administration. Archived from the original on 5 April 2012. Retrieved 2 December 2011.
- ^ Norwegian National Rail Administration (27 June 2008). "Spørsmål og svar" (in Norwegian). Archived from the original on 29 August 2012. Retrieved 24 January 2011.
- ^ Norwegian National Rail Administration (15 August 2005). "Dette er bygd på Sandvika-Asker" (in Norwegian). Archived from the original on 16 September 2009. Retrieved 24 January 2011.
- Norwegian National Rail Administration (6 June 2008). "Første lys i tunnelen" (in Norwegian). Archived from the originalon 2 June 2009. Retrieved 24 January 2011.
- Norwegian Broadcasting Corporation (in Norwegian). 24 January 2002. Archivedfrom the original on 4 September 2012. Retrieved 2 December 2011.
- ^ "Jernbaneverket Skaugumtunnelen Solstad - Asker JA1" (in Norwegian). Mika. Retrieved 9 September 2011.[dead link]
- ^ Rovick, Arne (6 July 2006). "1200 kilo dynamitt eksploderte i tunnelen rett foran Oddbjørn (39)". Verdens Gang (in Norwegian). p. 8.
- ^ Nordli, Olav (16 April 2008). "Suksess med strukturlyddemping" (in Norwegian). Norwegian National Rail Administration. Archived from the original on 18 September 2012. Retrieved 2 December 2011.
- Norwegian Ministry of Transport and Communications (1999). "Særskilt om Romeriksporten" (in Norwegian). Archived from the originalon 29 March 2012. Retrieved 2 December 2011.
- ^ Carstens, Halfdan (21 February 2011). "Norske tunneler" (in Norwegian). Geological Society of Norway. Archived from the original on 2 April 2012. Retrieved 2 December 2011.
- ^ Nordli, Olav (3 November 2004). "Sporlegging mellom Sandvika og Asker" (in Norwegian). Oslo Package 2. Archived from the original on 2 April 2012. Retrieved 2 December 2011.
- ^ Nordli, Olav (29 August 2005). "Sandvika-Asker åpnet" (in Norwegian). Norwegian National Rail Administration. Archived from the original on 25 March 2012. Retrieved 2 December 2011.