Lichtenholz tunnel

Lichtenholz tunnel
	South portal 2017
place	Birkach am Forst ; Zilgendorf
Number of tubes	1
construction
Client	DB Netz AG
start of building	2010
completion	September 2013
business
release	December 2017
North portal 2017
location
Coordinates
North portal	50 ° 10 ′ 48 " N , 10 ° 58 ′ 50" E
South portal	50 ° 10 ′ 19 ″ N , 10 ° 58 ′ 24 ″ E

Map with all coordinates: OSM | WikiMap

The Lichtenholz tunnel is a 931 m long tunnel on the new Ebensfeld – Erfurt line in the Lichtenfels and Coburg districts between the route kilometers 95.317 and 96.248.

The tunnel tube belongs to construction section 3110 (also called construction section Lichtenfels) of the new line, which lies between construction kilometers 9,090 and 15,144 and also includes the Kulch tunnel , the Mühlbach bridge Untersiemau and five overpasses as well as the earthworks on the open section. The award package to the NBS Lichtenfels working group had a contract value of 110 million euros. Construction began in October 2009 and was completed at the end of 2013. The costs are around 30 million euros.

The tunnel was inaugurated on June 2, 2010. Birkach am Forst struck . The tunnel sponsorship was taken over by Karin Seehofer, the wife of the Bavarian Prime Minister Horst Seehofer . The technical breakthrough was on September 2nd, 2011. On August 15th, 2013 around 2500 residents and guests visited the building. The cut in the terrain in front of the southern tunnel portal was fenced off.

Construction work

The tunnel was driven by dredging and blasting using shotcrete . The drive was carried out from the north portal to the south, the construction of the inner tunnel shell from south to north.

In the northern section, the tunnel crosses the uppermost part of the Middle Keuper , the so-called Feuerletten, over a length of about 300 meters . These are red to purple clay stones and clay marl stones, which are characterized by strong swelling behavior, i. H. Volume increase in the event of water ingress, are marked and can be sliding layers for landslides. It is considered to be the geologically most demanding tunnel on the new line.

The geological peculiarities encountered during the construction work required a modified construction and a construction time postponement of around six months. During the pre-cuts, slope dowelling measures had to be carried out using large bored piles with a diameter of 1.5 m and a total length of 3000 meters to ensure the stability of the embankments . 1200 meters were advertised. The stop wall at the north portal had to be secured with 4300 meters of anchors with a maximum length of 26 meters. The original plan was 2800 meters with a maximum length of 16 meters. The screen for the collision protection was also significantly more complex.

The excavation and the excavation of the cut between the south and north portal of the Kulch tunnel, east of Zilgendorf , were carried out at Großheirath on the Steinbruchsäcker landfill ( 50 ° 10 ′ 46 ″ N , 10 ° 58 ′ 27 ″ E ), a former clay pit of the company Gottfried, stored. 50.179444444444 10.974166666667