Restoration of structures

The condition of the historical flood ditch bridge at the federal road B 86 close to Reinsdorf drastically deteriorated over the years. Therefore, it had to undergo extensive renovation in 2010/2011. The department for the restoration of structures was awarded the contract to restore the 110-metre long sandstone bridge with its ten buttress arches as a homogeneous and durable supporting structure. In practical terms, this means that the old sandstone vault was completely maintained. However, it was renovated at selected points and it received a completely new superstructure. The job task entrusted to the Bickhardt Bau restoration specialists also included the renovation of the immediately adjacent, 10-metre long single bridge of the same construction type. Especially moisture penetrating the bridge structure from the top caused moisture penetration, cracks and other damage to this bridge, as well.

While the old road surface on top of the bridge was dismantled by means of diggers and road mills, the Bickhardt restoration specialists did an excellent job in the semicircular arches below the bridge. First, water jet technique was applied to remove the bituminous paint from the lower side of the bridge. Afterwards they removed loose material and started the reconstruction. Missing or brittle stones were replaced with new sandstones which were, to some extent, cut from other broken stones. In the area of the bridge pillars, they drilled holes in a specific pattern. Afterwards special mortar was injected into these holes. Then joints were cut by machine. They were extensively filled with mortar afterwards. In another work step, sandblasting was applied to uncover the sandstone and the network of joints evenly. A similar approach was used for the front sides where the brickwork was reconstructed as exposed brickwork. The superstructure was constructed afterwards. Traffic has flowed over the bridge since mid -2011 again.

After a construction period of eleven months, the Fulda bridge in Ludwigsau-Friedlos was reopened to traffic in May 2012: The historical sandstone bridge is the most important access to the district-owned household waste landfill Am Dickenrück. Since 1903, the bridge which is an arch structure has spanned across the Fulda river there. Since then, millions of vehicles have used the bridge, and the constantly increasing number of vehicles has considerably affected the bridge over the years. 

The load capacity of the sandy fill material between the arches varied considerably. In some areas of the bridge, it was able to withstand a load of 60 tonnes, but in other areas, it was obviously far too low. In order to restore the load capacity, the employees of the department for the restoration of structures removed all the old material from the arches and refilled them with lightweight concrete. The access areas to the bridge also needed to be reinforced. Due to the repair and strengthening, the renovated bridge has been designed to withstand a maximum load of 60 tonnes.