Timber-concrete composite bridge over the Kinzig near Haslach

As part of the construction of the new K5357 motorway near Haslach im Kinzigtal, a unique infrastructure project is being built in Germany: Germany’s longest heavy-duty bridge in timber construction. With a total length of 138.40 metres and four spans of 34 metres each, it is specially designed for permanent use under full traffic load.

In future, the bridge will connect Haslach and Fischerbach via the new route of the K5357 motorway, spanning the Kinzig river. Its load-bearing structure consists of five block-bonded glulam beams, which form a high-performance structure in combination with a reinforced in-situ concrete slab. The innovative timber-concrete composite construction method not only enables a high load-bearing capacity, but also scores points for its low use of materials and energy.

Great importance was attached to structural timber protection: Stepped cross-sections and the overhang of the carriageway slab reliably shield the structure from the weather and ensure the longevity of the load-bearing structure. In terms of design, the slender, technically precise structure blends harmoniously into the landscape. V-shaped tapered pillars and finely structured exposed concrete surfaces emphasise the design claim.

Designed in accordance with current standards for traffic loads according to load model 1 as well as for wind and earthquake loads, the structure fulfils the highest technical requirements. A well thought-out bearing concept, maintenance-friendly construction details and durable sealing systems round off the overall concept.