"Fascinated from the very beginning"
When he first saw segment production, Norbert Stricker was immediately intrigued. “I was fascinated from the very beginning by the challenge of using the concrete for tunnel construction in this way” explains the 43-year-old industrial engineer and master builder from Eisenstadt in Austria. Today, more than 100,000 segments and 6 years later, he can confirm his initial statement and back it up with plenty of experience.
After Norbert Stricker gained experience in the precast concrete industry and the field of planning, he managed the segment production for two international major projects and thus became a specialist for the lining of mechanically excavated tunnels.
In July 2013, Norbert Stricker took over the technical project management at MABA Fertigteilindustrie GmbH in Wöllersdorf near Vienna. About one year later, in September 2014, the Arge PTS Boßlertunnel (MABA and Porr) launched the segment production for the 9 km long Boßlertunnel in Aichelberg near Stuttgart. Stricker and his colleagues managed the building of the segment factory in the in the open countryside. More than 60.000 concrete segments weighing up to 16 tons each were planned to be precast in this factory. The tolerance specifications for the segments which should be installed by the tunnel boring machine “Kätchen” were very high: The team around Norbert Stricker had to build the segments with the accuracy of a tenth of a millimetre.
One year later, in October 2015, the segment productions for the Koralmtunnel project – construction phase KAT3 – was running at full speed. The lot KAT3 forms part of the 32km long railway tunnel between Graz and Klagenfurt and includes a section of 10.47 km which is being excavated mechanically and lined with concrete segments. The Arge PTS KAT3, a consortium of the companies MABA and Porr, ran their production in a 4,530 m² factory and produced on average 100 concrete segments per day on a carousel system from Herrenknecht Formwork. In December 2019, the total production of 42,000 segments was completed successfully.
We wanted to know from Norbert Stricker, what he considered the gratest challenge during the four year long production period in Kärnten, Austria. In addition to logistical issues such as limited space and high production output, the PTS-team had to follow the Austrian segment directives with values of a tenth of a millimetre. “In order to produce perfect segments, we needed an excellent interaction between the mould technology, the concrete supply and mixture, and the vibration system which can reduce the risk of blowholes to a minimum”, Stricker explains.
In a close and cooperative partnership, Arge PTS and Herrenknecht Formwork fullfilled the high requirements successfully. Herrenknecht Formwork adapted the entire production line to the space conditions and the planned output quantity. “The equipment from Schwanau worked out reliably as usual. In case of difficult challenges, we always managed to find a common solution.”, Sticker confirms with a look back to the production phase. But what happens with the high-quality equipment after the completion of a project? With the aim of reusing as many components as possible, Herrenknecht Formwork offers its customers a buy-back option for many parts right from the beginning of the project. Against this background, the teams from Arge PTS and Herrenknecht Formwork are examining possible future projects, where the equipment can be used for a second time after project-specific refurbishment. In this way, sustainable solutions can be found that all parties will benefit from.