The elevated road Elbmarsch (K20) is an elevated part of motorway A7 and, as important north-south axis, indispensable for Hamburg's city traffic as well as transit traffic. The bridge, completed in 1974, has reach the limits of its capacity and will be extended from six to eight lanes.
Between the partial structures, separated in directional lanes, is a gap of 10.5 metres which was reserved during initial construction for a future extension.
In this gap, the respective fourth lanes will be added to the existing prestressed concrete bridge. The existing structure will thus be maintained and renovated. To implement the connection to the existing bridge, composite concrete components are added to the old, prestressed concrete girders; the connection will then subsequently be done by joint connections with coupling of the transvers prestress.
Part of the contract is the additional final design for the renewal of ten mega pillars with prestressed concrete beams underneath the old bridge.