Post-tensioning system,
Bridge construction
Donaubrücke
consists of a prestressed and haunched T-beam cross-section, the cross-section height in the field is 1.5 m and increases to 2 m above the central support. Due to a special proposal, tendons with 31 strands St1570 / 1770, a cross-section of 4,650 mm² per bundle and a permissible prestressing force of 5 [...] the first time in Germany for the internal prestressing of a new bridge. 12 BBV L31 tendons with lengths of approx. 62 m were installed. Compared to the types usually used with 19 or 22 strands, the larger tendon units reduced the space required for prestressing in the concrete cross-section and concentrated [...] tension force in the superstructure cross-section. The lower number of tendons resulted in a better concreting situation for the cross-section. The prestressing steel strands were shot into the laid HR 115/122 ducts on the construction site with a hydraulic pushing device. The post-tensioning force was applied[...]