Architecture firm Gustafson Porter + Bowman was named the winner of a competition to redevelop the Eiffel Tower's “grand site.” The firm’s final design for the iconic site turns the traffic-isolated and shadeless area into a green space meant to be inviting both to tourists and locals.
The release of the model is the final step in a partnership between Autodesk and the City of Paris: Autodesk created a 3D model of the site surrounding the tower, so that the city could give the competing firms an accurate site model.
The collaboration started with a meeting: Nicolas Mangon, Autodesk’s VP of AEC Strategic Marketing, visited the deputy mayor of Paris and the then-governor of the Paris region, and showed off the capabilities of BIM and simulation. “I showed them how they could use BIM to simulate flooding in the city, if, at some point, they need to evacuate the Louvre and save the Mona Lisa if it gets flooded,” recalled Mangon. “They were amazed by what BIM can do at the city level.”
One possible area on which the two parties could collaborate was the neglected area surrounding the Eiffel Tower. While the tower attracts millions of visitors every year, the grounds are largely unshaded, feature awkward tourist lineups and unattractive anti-terrorist fencing, and are difficult for pedestrians coming from the nearby Métro station to access because of multiple lanes of traffic.
“There [were] three drivers for this project," said Mangon. "One is the 2024 Olympics. The second one is terrorism, because the city wants to make sure it's a safe place. Today, there are temporary measures in place, but it’s not the best customer experience. The third one is to actually attract Parisians to the site.”
Paris and Autodesk struck a bargain: Autodesk would create a detailed map of the current site, which it would give to the City of Paris to pass on to contractors bidding for the job. Then, the Parisian government would decide between these concepts to choose a final revamped look.
Connecting the Dots
The Autodesk team had a challenge ahead of it in creating an initial map. The site was a 1.5-mile area, including the tower, the Champs de Mars, and the Trocadéro Gardens across the Seine. It was also complicated by Paris’s stringent drone laws, which meant that the firm couldn’t get permission to use photogrammetric drones around the Eiffel Tower. Instead, it relied on ground-based LiDAR scanning to get an accurate picture of the area. The company scanned some of the less detailed areas with a scanner mounted on a truck and put static scanners in areas that needed more precision. Ultimately, Autodesk ended up with 10.3 billion points, with 342GB of point cloud data in total.
In creating its final model, the team also had help from preexisting geographical information system (GIS) data. The team reused a 3D model of the Eiffel Tower that had been put together years ago in order to look at how the tower’s shadows fall across the surrounding landscape depending on the time of day. That was an important detail, since one of the rationales behind the project was making sure that there would be more shade for people using the grounds.
After the data was collected, Autodesk hired business services company WSP to put together an intelligent model based on a similar project that the firm had completed in Chicago. WSP put together the model using Autodesk InfraWorks, Civil 3D and Revit.
When WSP was finished with the model, it was passed on to four architects competing for the contract: Gustafson Porter, AL_A and Quatorze-ig, Agence Terand Arcadis, and KOZ Architectes. All four companies based their new designs for the tower site on a simplified InfraWorks version of the original model, and all four firms released what Autodesk calls an “immersive visual experience” of their site plans.
It’s Easy Being Green
GustafsonPorter’s winning design fits an overall trend in Parisian infrastructure; a push toward making areas more pedestriancentric. In the press release, codesigner Kathryn Gustafson called the design “Paris’s largest garden,” featuring a green strip that bridges both sides of the river.
The most prominent new feature is the transformation of the Pont d’Iéna, which connects the Eiffel Tower to the Métro system, into a “green bridge.” Trees and pedestrians will replace asphalt and cars. “I thought it was a really important factor in the proposal,” said Mangon.
There will also be more green and pedestrian space throughout the area, including parks, pools and fountains. The Champ de Mars area will feature two new squares and a set of raised lawns, and there will be a pedestrian square called the Place de Varsovie around the preexisting Varsovie fountains. The square was created by routing traffic on the right bank quay into a tunnel.
While the site’s counterterrorism features aren't obvious on a first pass, there are built-in measures to decrease the likelihood of an attack and also make it easier for people to evacuate the area if necessary. Security gates near the tower make it harder to bring in items without having them checked, and a set of tall glass and metal walls around the base of the tower will replace the unattractive temporary barriers that were installed in 2016.
An overhead model of the new design shows off what its creators call a “green corridor” across Paris. (Image courtesy of Autodesk.)
According to Magnon, the team also used InfraWorks Mobility Simulation, which simulates how crowds are likely to move through spaces, to simulate how crowds might move in case of an emergency evacuation.
The How and the Why
The City of Paris predicts that having a BIM model of both the new and the old site on hand means that there will be fewer construction errors, and that the construction process as a whole will take less time. That’s important for an iconic site with a high visitor count.
The model has also given Parisians a vision of how one of their most iconic destinations could be renewed. That kind of vision is more important than ever, in the wake of the damage done to the iconic Notre Dame cathedral back in April. “In the midterm, my hope is that so many people will have a great experience seeing Paris [during the Olympics], especially in the context of Notre Dame,” said Magnon, who isn’t certain whether the city will be able to rebuild Notre Dame in time for the Olympics.
In the long run, Autodesk, Magnon, and the City of Paris all share the goal of creating a space that Parisians will be proud to call their own. “I hope my kids will live in Paris,” Mangon said, "and that someday, they’ll be able to look at the space and say, ‘My dad participated in this project.’”