First bridge structure using CPC slabs in the Hanover region

The district of Wennigsen has replaced a wooden footpath and cycle path bridge, which was over 40 years old, with a new bridge structure. The new bridge features a hybrid construction comprising three different materials. The substructure consists of a galvanised steel frame. A total of three CPC (Carbon Prestressed Concrete) slabs are laid on top of this, forming the deck. The CPC slabs are high-strength concrete components featuring rust-proof carbon reinforcement. The use of carbon reinforcement allows the concrete cover to be minimised, resulting in a very slender structure. The bridge is bordered on the sides by a 1.30 m high railing made of solid timber (in this case, larch). Following a structural analysis by SKI, the abutments of the old bridges were able to be reused. There are now six elastomeric bearings on the abutments, upon which the new bridge structure is supported on a floating basis. The chosen construction method represents a robust and particularly durable design. Holcim, the manufacturer of the CPC slabs, estimates a service life of 100 years.

Due to the limited space available, all components of the new bridge had to be transported individually to their final destination and assembled there. The bridge, which is 5.00 metres long and 2.10 metres wide, spans the Wennigser Müllbach and connects a park to a nursery.

SKI was contacted by the municipality of Wennigsen to carry out a structural analysis and produce drawings for a replacement building of identical design. As a special proposal, SKI put forward the construction method ultimately adopted, using a CPC slab. SKI was responsible for the design of the civil engineering works (phases 1 to 4), the structural engineering design (phases 2 to 5) and on-site construction supervision.

SKI would like to take this opportunity to express its sincere thanks to all those involved, in particular the municipality of Wennigsen, Co. Holcim, Co. MWM and Co. Gumba, for their constructive, focused and trusting cooperation. Without the collaboration between the client, the designers and the contractors, it would not have been possible to complete the project so smoothly within such a short timeframe. It took just six months from the start of the contract to its successful completion.