The Louis Vuitton Foundation for Creation, a magical place imagined by Frank Gehry at the request of Bernard Arnault, President of the LVMH group, is gradually taking shape in the heart of the Paris's Bois de Boulogne. The American-Canadian architect (Pritzker prize 1989), has designed a building wrapped with a big glass canopy (glass sails), comprised of assorted concrete facades in geometrical shapes, as original as they are complex, called icebergs... made in Ductal® using a unique process recently awarded by the French Concrete Industry Federation.
16,000 Ductal® panels, all different
"Several solutions were studied to produce these wall panels," explain Christian Reyne and Nicolas Paschal, deputy director and director of the project respectively for the project owner, the Louis Vuitton Foundation. "Metal and sprayed concrete were considered but we chose Ductal®, the only solution which met all our expectations in terms of finish quality, durability and mechanical resistance." The project demanded high quality requirements and aesthetic criteria in line with the image of the LVMH group: "The panels must be brilliant white, completely smooth and perfectly match the non-standard geometry of the structure."
Ductal® satisfied all of these requirements, but it was crucial to develop a process for producing the 16,000 wall panels, all with non-standard 3D geometry, so that they would match the curve of the 9000m2 façade. Producing 16,000 molds was clearly technically and financially unfeasible, therefore it was necessary to develop a new technological solution....
MSV: a completely new vacuum casting process
The solution was developed by Lafarge and prototype manufacturer Cogitech Design, in collaboration with project management consortium RFR/TESS. "The first discussions between Lafarge and project managers date back to 2006. Two years of development carried out in partnership with French company, Cogitech Design, were required to develop an appropriate implementation process and position Ductal® in relation to rival solutions," explains Thibault Lagrange, the Ductal® Project Management Engineer. The result was a unique vacuum casting process using a flexible mold capable of adapting to any curve, combined with a polystyrene template manufactured to the required geometry. The MSV (Moulage Sous Vide) process was patented by Lafarge in 2008. All that was needed now was to ensure the industrial feasibility
Bonna Sabla, a French concrete precaster familiar with Ductal®, took on the challenge of producing several series of prototypes. "The main issue we faced was keeping the mold sufficiently rigid while retaining the flexibility required to guarantee the strict accuracy of the geometric shapes, in compliance with the specifications of the project's managers, who challenged us throughout the process," says Patrick Mazzacane, Bonna Sabla's UHPC director. "We therefore optimized the MSV process so it could be used in an industrial context, which led to us winning the call for tenders as well as two innovation awards from the French Concrete Industry Federation: the Jury's Grand Prize and the Web-users' Prize." The prototype phase resulted in the production of the "First-run model" in September 2010.
Quality control plans worthy of the aeronautics industry
Since every part was unique, it was defined in a 3D digital file representing the identification sheet for each panel. This digital file made it possible to define the template's geometry and to produce the panel. Once each panel was produced, it underwent a series of quality controls: "A 3D geometric report is produced by a robot for each demolding," adds Patrick Mazzacane, "with a tolerance margin of just 1mm! The mapping is then stored on a RFID chip incorporated into each part." This ensures traceability and can be used during assembly and maintenance.
Industrial production of the Ductal® panels will begin this summer, at the end of a course. of development which has lasted 4 years. Assembly is due to begin in the fall of 2011, leaving Bonna Sabla just 12 months to produce the 16,000 iceberg panels... "In 2010, we manufactured 400 parts over the course of the year," says Patrick Mazzacane," and from March 2011, we will be producing no fewer than 100 a day!" One more achievement by this unprecedented architectural project.
To see Frank Gehry's model of this innovative project, visit:www.fondationlouisvuitton.fr