GEO5 and the 5th operating section of Prague metro Line A Sponsored

The station construction started by driving the right-hand and left-hand station tunnels. The so-called horizontal excavation sequence consisted of top heading and invert. The 300mm thick primary lining is in C20/25 shotcrete. Two hinges were artificially created in the structure designed to make easier breaking of the lining in the area of the central bay possible. When the excavation of the side tunnels had been completed, EPB shields driving the interstation sections were pulled through them. After removing all auxiliary structures required for the pulling of tunnelling machines through, the waterproofing system consisting of a ray-on membrane and subsequently the secondary lining were installed. Water-retaining concrete C30/37 was used for RC structures, or C45/55 concrete for columns and longitudinal beams.

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