Old castle tunnel
The tunnel Alteburg with 874 m length of the shortest road tunnel , the tunnel chain which contains the crest of the Thuringian Forest crosses. More tunnel of the chain are the Rennsteigtunnel , tunnel Hochwald and Berg Bock tunnel .
As part of the federal motorway 71 , located between the Gräfenroda and Oberhof junctions , the Alte Burg tunnel south-west of Geschwenda crosses the Alte Burg ridge. The west portal ends directly in front of the Schwarzbachtal viaduct , followed by the Wilde Gera viaduct and the Rennsteig tunnel to the south . A distance measuring system is located directly in front of the tunnel portals in each direction of travel. The tunnel has a constant gradient of 2.5% to the north. Construction began in 1998 and the tunnel breakthrough a year later. The interior work was carried out after the earth transport was completed and ended in 2002. The tunnel sponsor was former Family Minister Claudia Nolte . The total cost of the tunnel was around 27.5 million euros, making it the most expensive of the four tunnels at 15,900 euros per meter of tube.
construction
The northern tube has a length of 874 m and the southern tube of 866 m. The distance between the tubes is about 25 m. Each tube has a clearance height of 4.5 m and a clearance width of 9.5 m, which is divided into two 3.5 m wide lanes, edge strips of 0.25 m and emergency walkways on both sides of 1.0 m wide. The directional lanes are connected by two cross tunnels at a distance of 350 m. The tunnel was built with blasting and shotcrete lining according to the new Austrian tunnel construction method . The tubes were driven in parallel from the eastern portals. The standard cross-sectional area is 80.5 m². 160,000 m³ of excavated material accumulated and was installed in the subsequent sections of the route. The tubes are ventilated lengthways by jet fans , eight in the north tube and twelve in the south tube.
Specialty
130 meters before the breakthrough, an old, unknown, filled mine tunnel, presumably for manganese mining, was driven into during tunneling. This resulted in an ingress of 2000 cubic meters of mud. The interference zone had to be driven through in a complex manner under the protection of a pipe umbrella .
literature
- Federal Ministry of Transport, Building and Housing: Bridges and tunnels on federal highways 2004 . German Federal Publishing House, Berlin. ISBN 3-935064-28-4
Web links
Coordinates: 50 ° 43 ′ 0 ″ N , 10 ° 48 ′ 22 ″ E
