Crown bridge

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The narrower light opening of the new bridge (2018)
The new crown bridge at night.

The Kronenbrücke is one of the two oldest bridges in Freiburg im Breisgau . The wooden footbridge over the Dreisam was replaced by an iron structure in 1869. In 1902 the bridge was reopened as Friedrichsbrücke after flood damage . In the course of the car-friendly inner city ring, the structure was replaced by an oval-shaped double bridge. Since the construction was not suitable for the planned tram route , a new bridge was built, which was opened for private traffic at the end of 2018.

history

Wooden bridge (until 1869)

In the Middle Ages, there was a wooden walkway at the site of today's bridge . This was part of the trade route from Frankfurt to Basel , which , coming from Martinstor , ran along today's Garten- und Kronenstraße.

Gartenstrasse Bridge (1869–1903)

Garden road bridge

The wooden bridge was finally replaced in 1869 by an iron structure with a stone substructure. However, it did not achieve the desired stability and had to be rebuilt three years later after it collapsed as a result of a Dreisam flood. In 1876 it was connected to Bertoldstraße via the newly laid out Werderstraße (today: Werthmannstraße).

At the turn of the century, the city ​​planners saw the approximately 10-meter-wide bridge as "very narrow" because of the increasingly heavy traffic. Even if the flood of the century in 1896 - unlike the Schwabentor Bridge - was comparatively light, the underwashing showed that the structure at that time was not suitable for discharging large volumes of water. The Citizens' Committee of the City Council therefore decided to renew a total of six Dreisam crossings as well as additional investments in bank protection.

Friedrichsbrücke (1903-1967)

Friedrichsbrücke

The new bridge, costing 267,000 marks, was inaugurated in 1903 and was given the name Friedrichsbrücke on the occasion of the 50th anniversary of the throne of Grand Duke Friedrich I. The 16.5 meter wide bridge consisted of three segments that used common abutments , but were otherwise built completely separately. This was used to prevent vibrations from the roadway being transferred to the sidewalks.

The Art Nouveau railing made by the Armbrüster brothers consisted of artistic motifs of native trees and bushes, the branches of which reached to the supporting arch of the iron bridge construction. The grand ducal or Freiburg coat of arms was placed in the center of the railing . The conclusion was formed by mighty dragons and lantern holders made of white sandstone decorated with lion heads . The building was therefore also popularly known as the "Mother-in-Law Bridge". The railing was removed when the successor bridge was built and was later used for the Schnewlin Bridge ⊙ . With him, the nickname passed on.

  • Art Nouveau railing with dragons on today's Schnewlin Bridge

  • Grand Ducal coat of arms

  • City arms

  • Lantern bearer with lion heads

Oval-shaped double bridge (1967-2015)

Crown Bridge (2013)

In 1963 the city council decided to build a new oval-shaped double bridge. In connection with this, there were concepts for the "car- friendly city " which, in addition to the construction of the Mitte feeder, envisaged a four-lane expansion of Kronenstrasse to connect the city center. In 1967 the first bridge for 1.4 million was Deutschmark completed. It crossed the Dreisam west of the Friedrichsbrücke and was initially operated parallel to it. The city council finally decided to rebuild the rusted and under-laid Friedrichsbrücke for 1.67 million D-Marks and had its foundations blown up. The complete double bridge was finally opened to traffic in 1969 under the name Kronenbrücke. Because of its oval shape, it was popularly known as the elephant toilet .

Demolition (2015-2017)

Demolition of the eastern bridge on an auxiliary table (2016)

Since it was not possible for static reasons to run the tracks of the planned tram route over the existing structure, the decision was made to demolish and then rebuild the bridge in need of renovation as part of the overall project “Redesign Rotteckring”.

The bridge was therefore no longer passable for motor vehicle traffic since February 2, 2015 . For pedestrians and cyclists, a temporary bridge was installed east of the Kronenbrücke by the technical relief organization , which was released on June 22, 2015. The demolition began in December 2015. Old, unknown foundations were found. Due to a high pressure gas pipeline and incorrect calculation of the volume of the old bridge (1,800 instead of 1,100 cubic meters), demolition and new construction were delayed.

New building (2017-2018)

New building from below (2018)

With a one-year delay, the actual new building began in March 2017. The new bridge is no longer made of prestressed concrete , but of reinforced concrete with a steel substructure with nodes made of cast steel . This is unusual for the 40 by 40 meter expanse.

The light opening in the middle of the new bridge is no longer as oval as the old one.

After the new abutments were built came from March 2017 eight heavy-duty trucks from Steinach , each with a steel triangle with dimensions of 16 meters long, 5.5 meters wide and almost 4 meters high and about 25 tons, with a mobile crane was used precisely . They were welded to the knot with connecting pipes across the Dreisam. The formwork work for the concreting began in April. On the night of June 27th to 28th, 2017, the crown bridge was concreted with 70 workers in 13 hours. 150 loads of ready-mixed concrete of 20 tons each, equivalent to 1,200 cubic meters, were processed. Originally concreting was supposed to take place on the night of June 21st to 22nd, but it was too hot then. It then took four weeks for the concrete to dry and harden. After sealing, railing assembly and clearance for pedestrians and cyclists, the temporary bridge was dismantled at the beginning of December. Then the bike path ramp was built on the southeast corner.

Natural stone cladding with graffiti

While the road surface at the junctions began to be paved in the summer of 2018, the abutments were faced with natural stone, as with the previous bridge. And strangers also sprayed graffiti on the natural stones. The city filed a complaint. When asked by the Badische Zeitung whether this work, which cost 170,000 euros, could not be saved, the spokeswoman for the city administration replied that the old bridge was also clad in this way. Protection would now be applied to the stones to make them easier to clean. On December 12, 2018, the bridge was opened to motor vehicle traffic. On February 10, 2019, a train crossed the bridge for the first time and on the 11th, VAG began training its light rail drivers on the new route, which went into operation on March 16, 2019 according to the schedule. At night the new bridge is u. a. illuminated in blue.

Over a year after completion, the city and the Freiburger Verkehrs AG argue with the construction company Wolff & Müller about the costs, which they consider to be too high. Nobody names numbers, but it is an amount in the lower seven-digit range. If necessary, the dispute goes to court.

Web links

Commons : Kronenbrücke (Freiburg im Breisgau)  - Collection of images, videos and audio files
Commons : Schnewlinbrücke with railing of Friedrichsbrücke  - collection of pictures, videos and audio files

Photos from the Badische Zeitung

Individual evidence

  1. ↑ a b c Simone Höhl: The history of the Kronenbrücke: Dragons and mother-in-law Badische Zeitung, January 2, 2015, accessed on January 4, 2015.
  2. ↑ a b Redesign of Rotteckring - Kronenbrücke section , on the official website of the city of Freiburg, accessed on January 4, 2015.
  3. ↑ BZ editorial team: Photos: Torn down and rebuilt - the transformation of the crown bridge. Badische Zeitung, December 12, 2018, accessed on December 12, 2018 .
  4. ↑ a b Max Buhle: Bridges and footbridges . In: Baden Architects and Engineers Association, Upper Rhine District (Ed.): Freiburg im Breisgau. The city and its buildings . HM Poppen & Sohn, Freiburg im Breisgau 1898, p. 131-132 ( Scan - Wikisource ).
  5. ^ Peter Kalchthaler, Joachim Röderer: Freiburg: Passage forbidden. Badische Zeitung , August 25, 2012, accessed on April 22, 2017 .
  6. ↑ City map from 1931
  7. ↑ a b c Manfred Gallo: Dragons once protected the Badische Zeitung bridge , October 6, 2008, accessed on January 4, 2015.
  8. ↑ Temporary bridge open to cyclists and pedestrians. In: Badische Zeitung. June 20, 2015, accessed June 22, 2015 .
  9. ^ Simone Höhl: Freiburg: Bridge Day. Badische Zeitung, May 20, 2017, accessed on May 20, 2017 .
  10. ↑ a b Simone Höhl: Freiburg: Brückerücken. Badische Zeitung, March 11, 2017, accessed on April 29, 2017 .
  11. ↑ Simone Höhl: Freiburg: The new crown bridge has a special construction including a supporting structure with cast nodes. Badische Zeitung, January 4, 2017, accessed on January 4, 2017 .
  12. ↑ Simone Höhl: Freiburg: 150 concrete trucks for the new bridge. Badische Zeitung, June 20, 2017, accessed on June 29, 2017 .
  13. ↑ bz: Freiburg: Large construction site: due to the heat concreting Freiburg's new crown bridge postponed. Badische Zeitung, June 21, 2017, accessed on June 29, 2017 .
  14. ↑ Video: Michael Saurer, Falko Wehr and others: Freiburg: Construction work: Video: Construction workers concretize the new crown bridge. Badische Zeitung, June 28, 2017, accessed on June 29, 2017 .
  15. ↑ Simone Höhl: New construction sites are causing new traffic jams in Freiburg - Freiburg - Badische Zeitung. Badische Zeitung, July 24, 2017, accessed on July 28, 2017 .
  16. ^ Fabian Vögtle: Giant cranes remove temporary bridge - Freiburg - Badische Zeitung. Badische Zeitung, December 9, 2017, accessed December 10, 2017 .
  17. ^ Simone Höhl: Bridge free for cyclists and pedestrians - Freiburg - Badische Zeitung. Badische Zeitung, November 30, 2017, accessed November 30, 2017 .
  18. ↑ Simone Höhl: Where will be built in Freiburg in 2018. Badische Zeitung, March 7, 2018, accessed on April 27, 2018 .
  19. ↑ Simone Höhl: The 170,000 euro sandstone on the new crown bridge has already been sprayed with graffiti. Badische Zeitung, September 7, 2018, accessed on September 7, 2018 .
  20. ↑ Joachim Röderer: Kronenbrücke - new building goes into the final. Badische Zeitung, September 12, 2018, accessed on September 12, 2018 .
  21. ↑ Simone Höhl: The last weld seam of the new Freiburg Rottecktram is finished. Badische Zeitung, October 23, 2018, accessed on October 24, 2018 .
  22. ^ Simone Höhl & Joachim Röderer: The Freiburger Verkehrs-AG is testing the new Rotteck line. Badische Zeitung, February 10, 2019, accessed on February 11, 2019 .
  23. ↑ Joachim Röderer: Blue light on the new crown bridge. Badische Zeitung, December 18, 2018, accessed on December 18, 2018 .
  24. ^ Fabian Vögtle: This is how Freiburg celebrates its new city center. Badische Zeitung, March 16, 2019, accessed on March 17, 2019 .
  25. ↑ Simone Höhl: City and construction company argue for millions after the construction of the Freiburg Crown Bridge. Badische Zeitung, February 10, 2020, accessed on February 12, 2020 .

Coordinates: 47 ° 59 ′ 25.4 "  N , 7 ° 50 ′ 41.2"  E