Bietschtal bridge
Coordinates: 46 ° 19 ′ 23 " N , 7 ° 48 ′ 50" E ; CH1903: six hundred and twenty-eight thousand nine hundred and six / 130259
| Bietschtal bridge | ||
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| Convicted | Lötschberg mountain route | |
| Subjugated | Bietschtal gorge | |
| place | Raron | |
| construction | double-track steel bridge | |
| overall length | 110 m | |
| Longest span | 95 m | |
| Load capacity | 200 t | |
| Clear height | 78 m | |
| completion | 1913 | |
| location | ||
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| Above sea level | 1000 m | |
The Bietschtalbrücke is a double-track railway bridge on the southern ramp of the Lötschberg mountain route in the Swiss canton of Valais . The ascent from Brig to Goppenstein , the southern gate of the old Lötschberg tunnel , leads over the bridge .
location
The bridge spans the valley of the Bietschbach, which narrows into a gorge at this point. The maximum height of the bridge above the valley floor is 78 m. The bridge lies in the area of the municipality of Raron in the Rhone Valley, on whose area the south portal of the new Lötschberg base tunnel is located. The southern ramp of the old Lötschberg line overcomes a height difference of 540 m over a length of 25 km. The Bietschtalbrücke is roughly in the middle of this stretch. There is a tunnel on both sides of the bridge. On the valley side, the bridge has a narrow walkway.
Technical specifications
The steel bridge is 110 m long, including the massive connecting structures on both sides, it is 136 m. In this area, the tracks form an arc with a radius of 300 m. The cant is 10% and allows a maximum driving speed of 80 km / h. In the entire route area, the route increases by 22.2 ‰. The bridge weighs approx. 1400 t. The span of the middle arch is 95 m, the two connecting bridges are 35 m each. At that time, the steel parts in bridge construction were connected with rivets and not with welding technology as it is today. A total of 125,000 rivets were used in the construction.
history
The Bietschtalbrücke was built from 1910 to 1913. The builder was the Bern-Lötschberg-Simplon-Bahn, founded in 1906 . The bridge was mainly built by the steel construction company Albert Buss & Cie. built from Basel . A special technical challenge was the control of the forces in the required curved track layout. The Lötschberg mountain route, including the Bietschtal bridge, was initially built with one lane. Individual measures for a later double-track expansion have already been taken into account. The Bietschtalbrücke was also put into operation as a single-lane structure, although the central main arch was already designed for later expansion to double-lane. In the years from 1979 to 1985, extensive measures were carried out to reinforce and expand it to double track. The two previous single-track approach bridges, each with a 35 m span, have been completely renewed. The roadway on the valley side was lowered by 44 cm to increase the clearance profile in the tunnels. Rivets have been replaced by bolts with higher strength. New gusset plates and numerous other steel parts were attached for reinforcement. The bridge was also given new corrosion protection. As a result of the measures, the weight of the bridge increased from originally 1000 t to 1400 t.
Railway model
The Faller brothers , manufacturers of accessories for model railways, have the Bietschtalbrücke in two sizes in their range due to its striking and unique appearance . The model in nominal size H0 is 1100 mm long and 255 mm high, it is also double-track, but has a straight track.
Web links
Individual evidence
- ^ A b Jean Gut, Helmut Schmitt, Urs Graber: The Bietschtalbrücke of the BLS: Reinforcement and expansion on double track . Swiss engineer and architect. 1987. Retrieved September 4, 2014.
- ↑ Faller catalog . Retrieved September 4, 2014.