Forest tunnel

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Forest tunnel
use Railway tunnel
traffic connection Mannheim – Stuttgart high-speed line
place Forest
length 1724 m
Number of tubes 1
cross-section 96.06 m²
construction
Client German Federal Railroad
building-costs 85 million DM
business
operator DB network
release June 2, 1991
location
Forst tunnel (Baden-Württemberg)
Red pog.svg
Red pog.svg
Coordinates
Northwest portal 49 ° 10 ′ 2 ″  N , 8 ° 34 ′ 18 ″  E
Southeast portal 49 ° 9 ′ 41 ″  N , 8 ° 35 ′ 37 ″  E

The Forst Tunnel (formerly also part of the Forster Tunnel ) is a 1724 m long railway tunnel on the high-speed line Mannheim – Stuttgart north of Bruchsal . It is located on the territory of the Baden-Württemberg community of Forst and therefore bears her name.

Location and course

The tunnel, to which trough structures are connected on both sides, is located north of the community of Forst and runs in a south-easterly direction. The route runs in the western trough and large parts of the tunnel initially straight and head east in a right turn on, which also is the eastern trough structure. On the first few meters of the tunnel, near the north-west portal, the structure first crosses under federal motorway 5 , around 500 m north of the Bruchsal service area. In the further course, the district road K3524 is crossed.

The 1726.46 m long tunnel is connected to 993.66 m (west, 39.751 to 40.747) and 504.06 m (east, km 42.473 to 42.978) long trough structures. The total length of the structure is 3.22 km.

The route runs on the first 173 meters of the north trough (up to km 39.924) in a transition curve from a radius of 6845 m into a straight line. In the tunnel, from km 41.045, there is initially a transition curve, which turns into a right-hand curve of 7000 m radius up to km 41.360, which is retained until the end of the structure.

The gradient runs on the 819 m before the start of the western trough first in a gradient from 0.93 per mille. This is followed by a gradient of 10.1 per thousand over a length of 1120 m, which extends into the first meters of the tunnel (km 40.857). This is followed by a gradient of 2.57 per thousand over a length of 1473 m. Shortly before the end of the tunnel, at the transition to the eastern trough, begins (in km 42.330) a 694 m long ascent of 12.4 per thousand. To the east (from km 43.025) there is a 404 m long ascent of 2.5 per mille. The beginning of the two trough structures is each at a height of 110 m, the west portal at 98 m, the south portal at 102 m.

cross-section

The structure has a clear width of 12.30 m and a clear height of 7.81 m. The sole thickness is 1.0 m, that of the walls and ceiling is 70 or 90 cm. The base plate is anchored with 16 m deep steel girders and secures the structure against uplift.

The cover is around 2 m.

history

planning

According to the planning status of 1973, the route should be led in the forest area in a cut. The B 36 as well as the planned B 35 should be driven under and the federal motorway should be crossed. A depot should also be built to the south-west of Hambrücken (km 38.5) .

The plan approval procedure in section 5b ( forest , route kilometers 40.438 to 43.736) was initiated in April 1975. On May 6, 1976, the community of Forst applied to the Karlsruhe regional council to cancel the discussion date scheduled for May 30 and to open a regional planning procedure in order to regulate, among other things, the alignment of the new line. The public hearing took place as planned.

On July 9, 1979, a new plan approval procedure was initiated in Section 5b. The 129 objections raised were discussed on June 28 of the same year . The opinion of the regional council was presented on March 1, 1982. Five lawsuits were filed against the planning approval decision of April 27, 1982. It became final on June 1, 1984.

In 1983 the structure was planned to be 1,719 m or 1,727 m long, depending on the source. In mid-1985 the planned length was 1,727 m.

The structure is topographically unnecessary. Instead of an above-ground route (in the embankment), the Deutsche Bundesbahn opted for the more complex tunnel solution for several reasons: On the one hand, the community should not be cut off from a local recreation area to the north and the immission values ​​should be reduced. Furthermore, the expansion possibilities of the municipality , which is already spatially restricted by the A5 (in the west), the federal highway 35 (in the south) and the Rheintalbahn (in the east), should not be additionally restricted by the railway line running north.

Before the invitation to tender, various options for building the tunnel were examined and the chosen method was determined as the most economical solution.

construction

Construction work began in 1983. The tunnel went into construction as the second tunnel on the line, after the Pfingstberg tunnel .

While the groundwater was about one meter below the top of the ground, the roughly 20 m wide construction pit had to be excavated to a depth of 12 m. A lowering of the groundwater was also out of the question because of the highly permeable soil. An extremely complex construction process is due to these circumstances. The construction pit was excavated segment by segment (in lengths of around 80 m), a shell made of underwater concrete was created, the segment was finally sealed with sheet pile walls and then drained. Finally, the tunnel was constructed from waterproof concrete on vibratory injection piles . Each of the sections required around six weeks of construction. Building on this, the actual driving tunnel was built from prefabricated parts with a length of 8.80 m, which were connected to one another in a watertight manner with welded rubber joints.

In the professional world, the construction site received the title “Europe's longest submarine”.

A total of around 541,000 m³ was excavated and around 192,000 m³ backfilled. Some of the sand and gravel excavated from the excavation were also used for the production of the tunnel concrete.

The structure was concreted in 367 blocks, each 8.80 m long.

In 1985 a total investment of 83 million DM was expected for the tunnel. The construction costs, without the costs of the necessary recultivation, amount to 85 million DM (around 45 million euros, price as of 1991). (A source from 1985 gives this value as the award amount.) Around 90 people were employed on the construction site during the construction phase.

business

In July 2020, the points at the tunnel were renewed.

Web links

Individual evidence

  1. ↑ a b Deutsche Bundesbahn, project group Mannheim – Stuttgart (ed.): Route map for the new Mannheim – Stuttgart line 1: 100,000 . Folded map, Karlsruhe, June 1985.
  2. ^ A b Horst J. Obermayer: New routes for the InterCityExpress . In: Herrmann Merker (Ed.): ICE - InterCityExpress at the start . Hermann Merker Verlag, Fürstenfeldbruck 1991, ISBN 3-922404-17-0 , pp. 57-69.
  3. ↑ a b c d e f g h i j k l Deutsche Bundesbahn (Hrsg.): Tunnel Forst . 22-page leporello , Karlsruhe 1985.
  4. ↑ a b c d Deutsche Bundesbahn: New Mannheim – Stuttgart line - Forst tunnel. Overall view, km 39.751–42.978. Document dated July 26, 1982, with changes until June 11, 1985. File number 48N.84 Nbn (M / S) 3.801 (available at the Generallandesarchiv Karlsruhe ).
  5. ^ A b Project group M / S of the Bahnbauzentrale (publisher): New Mannheim – Stuttgart line: A concept for all of us . 28-page brochure from January 1986, Karlsruhe, 1986, p. 15.
  6. ↑ Deutsche Bundesbahn, Central Transport Management: Explanatory report on the planning of the new Mannheim - Stuttgart line . October 1973, file number 400a / 411a.4002 / 4123 Nv (Mhm – Stg) , p. 7 f; (available at the Generallandesarchiv Karlsruhe ).
  7. ↑ a b Erich Fein: New Mannheim – Stuttgart line: Commissioning in the Rhine Valley . In: Die Bundesbahn , issue 5/1987, pp. 381–393.
  8. ↑ Werner Hagstotz: Concern and collective action in rural areas . Verlag Haag + Herchen, Frankfurt am Main, 1981, ISBN 3-88129-475-9 , p. 270 f.
  9. ↑ a b Belter: Great progress in building the tunnels for the new lines . In: Der Eisenbahningenieur , 34, 1983, issue 12, p. 661 f.
  10. ↑ New Mannheim – Stuttgart line. Overview map 1: 100 000 . As of January 1983.
  11. ↑ a b c d Divers building a tunnel . In: Die Bahn informs , ZDB -ID 2003143-9 , issue 3/1985, p. 7 f.
  12. ↑ a b Heinz Dürr , Knut Reimers (Ed.): High-speed traffic . 1st edition. Hestra-Verlag, 1991, ISBN 3-7771-0234-2 ( Yearbook of Railways , Volume 42), p. 119.
  13. ^ Hans-Wolfgang Scharf: The railway in Kraichgau. Railway history between the Rhine and Neckar . EK-Verlag, Freiburg (Breisgau) 2006, ISBN 3-88255-769-9 , p. 196 .
  14. ↑ KW29. In: bauprojekte.deutschebahn.com. Deutsche Bahn, July 20, 2020, archived from the original on August 25, 2020 ; accessed on August 25, 2020 .