MSG’s LTM 1650-8.1 dismantles 75-year-old bridge in Lauffen am Neckar

The single-lane bridge, which linked the densely built old town of Lauffen am Neckar in Baden-Württemberg with a small island across a 40-metre-wide canal, had reached the end of its service life: its load-bearing capacity no longer met structural requirements. Replacing it was anything but routine. The built-up surroundings left very little room to position a large mobile crane, and the ground that was available sloped away towards the water.

Supports beyond the edge

MSG Krandienst solved the set-up problem by placing the crane right at the top of the bank and taking its two water-side outriggers beyond the actual working surface. They were propped on large steel cylinders standing on concrete foundations roughly four metres below the crane — an unusual sight even for seasoned crane watchers. The auxiliary support cylinder under the rear of the carrier helped steady the rear outriggers on the sloping road during rigging.

“The topography on site severely restricted our options for setting up the mobile crane. Thanks to its compact design, the LTM 1650-8.1, with its high lifting capacities, was the perfect machine for this job.”

— Christian Spreuer, project planner for large cranes, MSG Krandienst

The crane was rigged with a 35-metre luffing jib and 175 tonnes of counterweight. Its first task was to hoist a temporary footbridge across the canal; it also swung the construction machines needed on the island over the water on its hook, setting them down safely at a radius of 50 metres.

Arch cut into five segments

Once the bridge superstructure and deck had been removed section by section, the massive supporting arch was cut into five segments with concrete saws. While the sawing went on over several days, a scaffolding-topped pontoon beneath the arch carried the structure; its height could be trimmed by flooding or pumping out the pontoon chambers. The LTM 1650-8.1 then lifted the segments out one by one. The heaviest was the apex of the arch at just under 44 tonnes, handled at a radius of more than 36 metres.

VarioBallast earns its keep

With load cases spread across radii from 26 to 50 metres, the crane’s continuously adjustable VarioBallast system let the operator match the ballast radius to each lift and keep the job moving. The Lauffen crane is one of two LTM 1650-8.1s in MSG Krandienst’s 55-vehicle fleet, which also includes two LTM 1750-9.1s. The crane hire and project logistics company, based in Kehl on the Upper Rhine, employs 175 people together with its French subsidiary MSG Levage.