In central Paris, a Liebherr MK 88-4.1 mobile construction crane operated by the Ponticelli group of companies repaired and reinstalled a damaged public artwork on the Pont-Neuf, the oldest bridge in the city. The work involved 'La Caverne du Pont-Neuf,' an installation by French artist JR.
The temporary artwork pays tribute to the legendary wrapping of the Pont-Neuf by artists Christo and Jeanne-Claude, first installed in 1985. The inflatable structure stretches roughly 120 metres. In early June, violent gusts of wind and hail damaged parts of its outer shell.
Ponticelli, a French lifting and industrial services company, developed a lifting solution within hours of the damage. "We were on site just a few hours after the damage occurred to work out the best technical solution together with the client," said Louis-Arthur de Quatrebarbes, head of the handling and lifting agency at Ponticelli. "As well as repairing the tarpaulin, we had to carry out a lifting operation safely in almost constant wind and under considerable time pressure."
Space on the bridge was tight, and the site welcomes a large number of daily visitors. Load-distribution plates were used to reduce ground pressure, while safety and traffic management measures kept the operation secure.
The team had originally planned to use a larger Liebherr mobile crane, but the confined conditions led it to bring in the MK 88-4.1 instead. Its 45-metre-long trolley jib reached all the damaged areas of the structure. The four-axle design made it easier to relocate from one side of the bridge to the other, where storm damage had also occurred, and its short set-up time and compact outrigger system further supported the work.
The crane cab could move at working height, giving the operator a clear view of the approximately 18-metre-high structure and the rope access technicians. Boom-mounted spotlights lit the work area during night-time operations.
The repairs were completed over four night shifts, with damaged fabric sections weighing between 200 and 400 kilograms lifted and reattached in collaboration with rope access technicians. Because the site sits in a wind corridor along the River Seine, weather conditions were monitored continuously, and the crane operator and rope access technicians stayed in radio contact throughout.
Before work began, the team carried out site inspections, load calculations and collision analyses of the surrounding buildings. A 360-degree test then confirmed the planned crane positioning.
For Ponticelli, the project went beyond a conventional lifting operation. "We are proud to have been part of this work of art," de Quatrebarbes said. "To quote JR: 'The installation of the artwork is part of the artwork' — and so is the crane. The visually striking deployment of the MK crane created a magical moment."
With the Pont-Neuf deployment, the Liebherr MK 88-4.1 demonstrated its strengths in demanding inner-city projects, where heritage conservation, confined spaces and a high level of precision require a combination of reach, compactness and flexibility.