“Arboretum”, a park with 1,000 planted trees and modern workplaces surrounded by an abundance of wood is the vision for Europe’s largest timber campus in Nanterre near Paris. Ten Liebherr EC-B series tower cranes are involved in the 650 million Euro project designed to create a new connection between nature and the workplace and is sustainable thanks to its solid wood construction.
The “Arboretum” project on the banks of the Seine will provide 125,000 square metres of office and service space and will be mostly built of solid wood. The offices are set to be spread over five buildings and each of them will be named after a tree: Almond, Pine, Cedar, Fir and Spruce. A park, a fruit and vegetable garden for the use of campus restaurants, and two renovated industrial buildings will complete the area. Measures designed to reduce the site’s carbon footprint include the reuse of materials, bioclimatic architecture and a geothermal system that will cover up to 80 percent of heating and cooling requirements.
GCC, a longstanding customer of Liebherr, has two 220 EC-B 10s, two 250 EC-B 10s, one 250 EC-B 12, two 285 EC‑B 12s, two 340 EC-B 12s and one 370 EC-B 12 in operation on the project. The jibs in use are between 47.5 and 60 metres in length. Hook heights range from 41 to 59 metres. As a result of these configurations and their flat-top design, the cranes can rotate above each other without encountering any problems. The transport and assembly-optimised cranes can, depending on the model, lift a maximum of ten or twelve tonnes. A 280 EC-H 12 high-top crane is additionally in use for the construction of the service centre.
Having as many as ten cranes on a construction site requires precise planning for efficient site operation. The top-slewing cranes, which will remain in operation until mid-2023, have to be coordinated with one another so that they don’t interfere with each other’s lifts. To ensure optimal safety, all cranes are equipped with an anti-collision system from the French manufacturer AMCS Technologies. The machines also include LiUP operator lifts, which particularly benefit crane operators and service engineers working at high hook heights, as is the case here. LiUP is designed to transport two people or a load of 200 kilograms. It gives crane operators quick access to their workplace and spares service engineers a strenuous climb during maintenance work.
Precise positioning
The construction of the new office buildings involves 20,000 cubic metres of wood from sustainably managed forests, as well as 55,000 cubic metres of concrete. All loads, some of which weigh several tonnes, have to be moved, and this is where the Liebherr tower cranes come in. The top-slewing cranes are being used for positioning timber and concrete elements such as posts, beams, columns, staircases and lifts. This work is supported by the Micromove fine positioning mode. The assistance system makes perfect use of Liebherr’s own high-performance drives so that loads are moved with precision over the course of several minutes and positioned with accuracy. This protects precast filigree concrete parts and existing constructions on site.
Comprehensive service
Most of the cranes are new machines that GCC has secured under a leasing agreement. “Leasing means that customers always benefit from the latest cranes,” explains Sébastien Chalvet, Liebherr Key Account Manager for the Île-de-France region. Liebherr-Grues à Tour is responsible for overall fleet management, “Working this way ensures that cranes are perfectly maintained for maximum availability, and that we can guarantee our customers the highest possible safety standards.”
