Renewal of Railway Bridge over River Oker, Goslar

Railway bridge Oker is a 4-span bridge leading a double-tracked, non-electrified main line over river Oker. The structure is a on oblique, semi-integral reinforced concrete frame with continuous ballast bed erected in a highly sensitive area in terms of hydrology and nature protection.
The 4-span superstructure is connected bending-stiff to the piles; connection to the abutments in longitudinal direction is floating and fixed in transverse direction. To optimise flow through in case of floods, the substructures on footings are oriented towards the flow direction during a flood.  The entire structure was prefabricated in an elevated position next to the actual location and launched into its final position during an 8-week total closure incl. construction of the abutments in watertight excavation pits (sheet pile boxes with underwater concrete base).