Road bridge over the TersluisBlock girder bridge as the entrance to the national park

On behalf of HessenForst and the Kellerwald-Edersee National Park, a new bridge was built in Vöhl-Asel to replace a dilapidated existing structure. The original bridge connected the K32 district road with a car park for hikers and formed the ‘entrance gate’ to the national park, which is heavily frequented by tourists. Due to serious damage, it was recently completely closed to motorised traffic.

The new bridge restores this important connection – for hikers, cyclists and also for forestry vehicles up to 12 tonnes. A single-span, double-span slab girder in timber-concrete composite construction was chosen as the supporting structure, which impresses with its robust, sustainable construction and clear design.

The main beams made of glulam (GL28h, 0.36 m high) are prefabricated at the factory and connected to a 0.16 m thick concrete carriageway slab (C 45/55) to form a slender superstructure (total height 0.52 m). The force-locked connection is made using cerves (3.5/15 cm) and Halfen reinforcement anchors with a maximum centre distance of 63 cm.

The supporting structure is designed as a protected timber bridge in accordance with DIN EN 1995-2/NA. The waterproofing is carried out with a reaction resin bonded thin layer system (RHD), the transitions to the substructure are carried out with the Migua Migutan system. Concrete overhangs and targeted structural timber protection permanently protect the load-bearing timber components from moisture and the effects of the weather. Chemical wood protection is therefore not required.

The ends of the building are edged with greywacke paving, which creates a flowing transition to the surroundings. The design is complemented by a restrained steel railing with filler rods made of branched robinia wood – a detail that harmoniously integrates the bridge into the landscape.