Last summer, Metrostav workers carried out the ninth and final launch of the steel structure, which is over 900 metres long and weighs over 7,000 tonnes, thus connecting the two banks of the Gottleuba Valley. They then lowered it from the launch position to the final position, which meant moving it 1.5 metres downwards. All this took place 70 metres above the ground. However, the most complex stage of the construction work is still to come in the following weeks, when the bridge builders will connecting the concrete pillars in the valley to the bridge’s supporting structure.
“After lowering the structure, we always had to align the pillars that were deflected by the launch to the relevant axis. To do this, we devised a unique process of straightening using horizontally mounted hydraulic cylinders and an additional steel beam inserted to form a joint. The final fixed connection between the pillars and the supporting structure will now be made in the form of concrete ramps that extend on both sides of the pillars for a length of 25 metres. At present, we have lifted the auxiliary structure to a height of over 50 metres, which is again unique and will enable us to hold a pillar and the supporting structure still, so that they do not rotate while the concrete sets,” explained Marek Foglar, construction director at Metrostav. The builders will repeat this unusual activity a total of five times and, at the end of the summer, they will be able to follow up with the concreting of the bridge deck on the bridge’s final structure and perform the finishing works.
The bold architectural design literally has the parameters of a model, and it was this “narrow waist” that required the project to be redesigned and construction delayed for several years. The bridge pillars are so slender that in some places the concrete reinforcement had to be divided into up into seven rows. As a result, the steel in the concrete reached a density of 600 kilograms per cubic metre, more than double the ordinary value. The bridge’s construction will consume a total of 7,000 tonnes of structural steel, a record 25,000 concrete reinforcement couplings and 12,000 cubic metres of concrete.
The new bridge in Pirna crosses a dense urban development, similar to Nusle Bridge in Prague. Local residents therefore had a unique opportunity to watch the spectacular launches live. The giant steel structure from Metrostav’s workshop in Horní Počernice completed a total of nine of them between 2023 and 2024, each time facing many opponents from the world of physics. “To give you an idea: A single launch ordinarily took ten hours and reached a speed of 24 metres per hour. The most tense was the launch over the longest 140 m field. The slender structure bent up to six metres at the tip of the launching nose!” revealed Foglar.
The Gottleubatalbrücke bridge is part of the Pirna road bypass. It will have a total of three lanes and will connect the road from Bad Schandau to a feeder to the A17 motorway. Once completed, it should speed up the journey from Děčín via Hřensko to this area and improve not only regional, but also cross-border transport services.
A consortium called ARGE Gottleubatalbrücke, consisting of the Czech company Metrostav and its affiliate BeMo Tunnelling, has been building the bridge for the investor DEGES since 2018. The total investment amounts to CZK 4.5 bn.
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
