The reconstruction of a key bridge destroyed during the 2021 floods in Germany’s Ahr Valley has reached a major milestone, with two Liebherr LTM 1750-9.1 mobile cranes completing a complex 105-tonne tandem lift.
The cranes, operated by Richter Kran und Schwerlast GmbH, installed major bridge components and a steel structure for the new Landgrafen Bridge in Bad Neuenahr-Ahrweiler. The original bridge was destroyed during the devastating floods that struck the Ahr Valley in July 2021.
Working for construction company Leonhard Weiss GmbH & Co. KG and heavy haulage and crane company Dietmar Floßdorf GmbH & Co. KG, the two cranes lifted a 105-tonne bridge section at a maximum radius of 38 metres.
Both LTM 1750-9.1 cranes were configured with 28-metre luffing jibs and 204 tonnes of counterweight to provide the capacity required for the precision lift.
The project presented significant challenges due to the limited space available on the banks of the River Ahr. The cranes had to be positioned close together, while a triangular spreader beam was used to distribute the load evenly between both machines throughout the lift.
The main lift was scheduled for 4am to take advantage of cooler temperatures and minimise the thermal expansion of the steel bridge section.
At higher temperatures, expansion could have prevented the bridge girder from fitting accurately into its designated supports.
“The team and everyone involved did an excellent job. The operation went ahead without any complications or incidents – exactly as planned,” said Thorsten Mahlberg, project manager at Dietmar Floßdorf GmbH & Co. KG.
The complexity of the project extended beyond the lift itself. The first crane was assembled before assisting with the erection of the second crane. During the tandem operation, operators had to ensure the load remained evenly balanced across the triangular spreader and both cranes at all times.
“A specialised operation in very confined spaces. A major challenge – but in the end, everything went to plan,” said Manuel Bergmann, crane operator of the blue LTM 1750-9.1.
“We had to work with great concentration and precision to keep the load on the triangular crossbeam and on both cranes constant. I’m very relieved that everything went according to plan,” said Michael Schmieder, operator of the white LTM 1750-9.1.
Following completion of the main bridge assembly, one crane was dismantled while the second was relocated to the opposite side of the river to complete the remaining work.
The successful lift demonstrated how careful planning, experienced operators and high-capacity crane technology can deliver safe and precise results in challenging conditions.
