Preparation for Driving the Ejpovice Tunnels is in Full Progress

The first segment lining ring for the Ejpovice railway tunnels, which form part of the modernized railway line Rokycany – Pilsen, has recently been manufactured by Metrostav personnel in West-Bohemian Prefa Dýšina near the construction site. Production started after successfully testing the steel-fiber-reinforced concrete precast components by the Klokner Institute of CTU Prague. Individual components manufactured by Metrostav (tubings) received the top rating and fully complied with all pressure and bending tests under the relevant standards. They are thus approved for use in this complex project which is about to start. Each ring with an outside diameter of 9.5m consists of seven basic components and one additional (binding) component. The total weight of the complete ring is 60 tons. A single ring is two meters long. Therefore, about 2,000 such assemblies will be required for each approximately 4km long single-track tunnel under the Homolka and Chlum Hill formations. This railway section is being modernized by the Metrostav joint-stock company which succeeded in its public tender offer with its construction project based on the state-of-the-art TBM technology. This safe and efficient tunneling method was last used by Metrostav, the largest Czech civil engineering company, on the V.A metro line where the Tonda and Adéla TBM machines, which had about 6 meters in diameter, completed single-track tunnels with a length of 8,354m (2x 4,177m) in about 20 months. Two single-track railway tunnels will be constructed on the Rokycany - Pilsen railway line, each with a length of 4,150m. The total length of this section will thus be reduced by approximately 6,100m. It will be driven by a larger sibling of the above-mentioned units, which will have a shield diameter of almost 10 meters, will be 110 meters long, and will weigh 1,800 tons. So far nameless, this unit with serial number S-799 is currently subject to the demanding factory acceptance process on the Herrenknecht premises in Schwanau, Germany. The first components of the machine will arrive at the construction site near Kyšice (Ejpovice) in September. Metrostav's engineers, who had to postpone their work by almost a year due to archeological findings, are currently preparing the site where the machine will be assembled to start driving (the entry portal). The driving work should commence in December this year. After the machine finishes driving the first tunnel, it will be partly disassembled and moved back through the completed tunnel to the entry portal in order to start driving the second tunnel. If everything goes according to plan, both tunnels should be finished before the end of 2017. The speed of trains in this section will increase up to 160kph, and travel time from Prague to Pilsen will decrease to less than one hour.