The Laerdal Tunnel was built during a five-year period from 1995-2000. It is an important link in the ferry-free road connection between the Bergen area and Eastern Norway, including Oslo, and is especially significant for winter traffic, when the high mountain passes are closed, or subject to closing, because of snow.
This tunnel is not only the world's longest, 24.5 km, but also the world's most uniquely constructed tunnel with exceptional security features. An access tunnel of 2.1 km was built from a side valley, Tynjadalen, 6 km from the Laerdal side. This enabled the crews to drill from four sites, which shortened the construction time.
This access tunnel also serves as an extraction tunnel for the ventilation system, and made it possible to deposit the excavated rock on the Laerdal side in an environmentally secure area.
High air quality in the tunnel is achieved in two ways, by ventilation and purification. Large fans draw air in from both entrances, and polluted air is expelled through the ventilation tunnel to Tynjadalen. The Laerdal Tunnel is the first in the world to be equipped with an air treatment plant, located in a 100-meter cavern 9.5 km from Aurland, that removes both dust and nitrogen dioxide from the tunnel air. Two large fans draw air through the treatment plant, where dust and soot are removed by an electrostatic filter. Then the air is drawn through a large carbon filter which removes the nitrogen dioxide.
To support and strengthen the ceiling and the walls of the tunnel, 200,000 steel bolts of up to 5 meters in length have been used, and 35,000 square meters of concrete has been poured!
In order to break the monotony of a 20-minute drive, the tunnel has been divided up into four sections by creating three large caverns, or mountain halls, 6 km from each end and one in the middle. Special attention has been paid to the lighting. Whereas white light is used in the tunnel itself, the mountain halls are equipped with blue and yellow light. This gives one the illusion of driving into daylight every 6 km, and the golden light along the floor gives the illusion of sunrise! To keep the drivers from being inattentive or falling asleep, and thus causing head-on collisions, each lane is supplied with a loud rumble strip toward the center!
extract from: http://www.bergen-guide.com/538.htm
Critiques | Translate
davido (1982) 2005-05-16 6:28
Very strange shot but I like it tough. This is just incredible what you mention in your note : 24,5 km! And the lightenings...
Yosibu (206) 2005-05-16 6:32
I liked the colors Sylwester and from your note it's appear to be a real technological achievement... Good work thank you for sharing
bebel (7571) 2005-05-16 7:08
hello, strange shot but it is interesting to learn about this tunnel in your note.
good technical job to obtain this "night" shot !
Cruize (0) 2005-05-16 7:20
Hi Sylwester, I like your tunnel image and you note is very good too. The colours are great. I'm wondering how you took this photo. Were you in a car or did you hop out and take it? Nice image...sorry my smilies have run out, but I will be back when they are.
jajko (775) 2005-05-21 9:23
those composition is realy good. nice shadows and great interesting colours... and this little lights on smart constructions...
well done!!! ist impressive!
- Copyright: Sylwester Arabas (slayoo) (644)
- Genre: Places
- Medium: Color
- Date Taken: 2003-08-00
- Categories: Transportation
- Camera: Nikon Coolpix 995
- Details: Tripod: Yes
- Photo Version: Original Version
- Travelogue: Scandinavia VII/VIII 2003
- Date Submitted: 2005-05-16 6:26