The gathering took place at the southern end of the Fortification Tunnel near Dead Lake on the outskirts of Trutnov. After the opening speeches, Archdeacon Ján Kubis of Hradec Králové blessed a wooden statue of St. Barbara. The patron saint of miners was then placed in a chapel at the entrance, where, according to tradition, she will symbolically oversee the safe course of the work.
Together with the Poříčí Tunnel, the Fortification Tunnel is the most demanding part of the 21-kilometre section of the D11 motorway between Trutnov and the Polish border, which is being built by the association of MI Roads, Doprastav, Subterra, Metrostav TBR and Duna Aszfalt.
“Construction of the Trutnov – national border section of the D11 includes not only two tunnels, but also, for example, 28 bridge structures and 10 noise barriers. A full quarter of the new motorway will be on bridges or in tunnels. We are working here in difficult terrain and extreme weather conditions, so the construction project is a real challenge for all members of our consortium,” said Zdeněk Ludvík, director of MI Roads, speaking on behalf of the contractor.
Both two-lane tubes of the Fortification Tunnel will have the same length of 492 metres. Originally, the Poříčí tunnel was to be the first to be excavated, but due to the geological conditions found, the work was rearranged and excavation of the southern portal of the Fortification Tunnel started last September. The excavation itself will take less than a year, after which the excavation work will move to the Poříčí site.
“Excavation will be carried out mainly by blasting in combination with the New Austrian Tunnelling Method (NATM). Continuous evaluation of the geological conditions and immediate stabilisation of the excavations using primary lining is crucial. This allows us to proceed safely even in the complicated massif that is typical for this area,” said Aleš Gothard, director of Metrostav TBR.
The method of gradual division of the profile into smaller cut-outs is used and they are continuously stabilised using primary lining made of shotcrete and bolts. The work will be carried out under continuous monitoring of the rock massif. It will be followed by the implementation of the secondary lining, mostly made of unreinforced concrete with foil waterproofing. The excavation area of each tube is 90 m².
The tunnel will be excavated continuously, day and night, including weekends. This requires a sufficient number of skilled technicians and workers. Approximately 120 workers will be on site during the period when work on both tunnels is taking place simultaneously.
“We’re glad that after many years that did not favour investments in underground structures we can build motorway tunnels in the Czech Republic again. Moreover, this project is a good example of cooperation in our group – three companies from the Metrostav Group are involved. We are making use of both the extensive experience of our experts and various types of our own mechanical equipment,” said David Cyroň, director of Division 1 at Subterra.
Contact Details
Radim Mana
Metrostav Group Spokesman
Metrostav a.s. Koželužská 2450/4 180 00 Prague 8
T 266 019 715, M 601 110 376
radim.mana@metrostav.cz
