VIDEO: Contractor demolishes 70-metre-high bridge
By Leila Steed16 May 2023
Demolition and dismantling company Richard Liesegang has demolished a 70-metre (230 ft) high motorway bridge in the North Rhine-Westphalia region of Germany.
The A45 Rahmede Viaduct, which measured almost 455 m (1,492 ft) in length and 31 m (101 ft) wide, was part of the A45 Sauerland motorway running between Frankfurt and Dortmund. It spanned a narrow valley, standing above the village of Rahmede near Lüdenscheid in North Rhine-Westphalia.
Closed to the public in 2021 after falling into disrepair and scheduled for demolition by motorway operator Autobahn GmbH, the Rahmede Bridge was taken down using 150 kg (330 lb) of explosives placed in over 2,000 charge boreholes on the bridge’s supporting columns.
Due to the close proximity of the houses and the narrowness of the valley it spanned, the Liesegang’s blasting experts took extreme care to engineer a detonation that would ensure the bridge collapsed straight down into a drop bed, weakening its five double-columns to prior to the blow down to guarantee a precision collapse.
Liesegang also erected a ‘wall’ of stacked shipping containers filled with sand and water to shield residential properties situated practically underneath the bridge from the blast and the resulting 17,000 t of concrete and steel rubble and debris.
Large crowds of spectators gathered on a hillside to watch the felling of the viaduct, some of whom had also witnessed its construction 60 years ago.
Built in the 1960s from a single main structure, the bridge was originally designed to carry the 25,000 vehicles that were predicted to be using it by the 1980s. By the time it was closed in 2021, the load had risen to around 64,000 vehicles, including around 13,000 trucks.
The Rahmede Bridge was just one of 60 viaducts on the A45 Sauerland route that need to be taken down. According to media reports, around 4,500 bridges across Germany are in need of renewal.
Liesegang has been involved in a number of demolitions on the A45 route to date. Part of a major infrastructure upgrade, the company previously took the second section of a 350 m (771 ft) viaduct near Eisern, and in just a couple of weeks’ time it is due to demolish the Sterbecke viaduct near Schalksmühle.
The construction of a replacement bridge is expected to start later this summer, with completion currently scheduled for 2026.