Mammoet helps in the installation of a new bridge over the Haarbach Valley in Germany. The new steel composite bridge replaces the original structure built in 1956, which had become unsafe for use.
Located on the A544 highway near Aachen, Germany, the Haarbachtal bridge is a crucial connection between Aachen and Cologne. Damage to the old bridge’s structure had limited traffic flow to a single lane each way and ultimately led to its closure. The replacement project, spearheaded by Mammoet in collaboration with AMAND Bau NRW, necessitated innovative solutions to minimise construction time and disruption.
Mammoet’s assignment involved launching two bridge structures, each weighing 1,340 tonnes (t) and measuring 160 metres (m). The engineering challenges were significant, with the bridge needing to be launched at a 2 per cent downward angle. Additionally, the new abutments and pillars were positioned at a 30-degree angle, requiring precise planning and execution.
The dismantling of the old bridge took place in January 2024, using controlled explosives, after which the new substructures were constructed on-site. By December, installation of the new bridge structures commenced. Mammoet utilised Self-Propelled Modular Transporters (SPMTs) to transport and position the structures, eventually lowering them onto newly fabricated pillars and abutments using a complex jacking system.
To stabilise the structures, temporary towers were erected, and Mammoet’s Mega Jack 800 system was employed, involving intricate bracing and stand jacks to manage the launch’s force dynamics. The approach to build skid tracks allowed for efficient movement of jacking towers, facilitating the installation of the second bridge structure with minimal delay.
Despite adverse weather and a busy construction site, the project was completed in 22 months, with each substructure taking only one and a half days to install.
This construction was made possible by prefabricating the bridge components on site at a regular working height, enhancing safety and efficiency.