Built in 1970, the Aurore tower is one of the first towers to be built in La Défense. Disused for years, a time promised to be demolished, the Aurore tower will finally be heavily restructured to come back to life:

  • A 6 levels elevation will increase the superstructures number of floors from 27 to 33 levels.
  • The 5 infrastructure levels and the hall level will be fundamentally reorganized (change of destination, modification of the stairs, etc.)
  • To adapt to changes to the elevators and technical bodies, the interior of the central core will also be completely revised.




Located next to the tower, the former BNP branch building, on the other hand, will be completely demolished and will be replaced by a “pavilion” which will bring together a multitude of services on eight levels (coworking, business center, auditorium, etc.).




Complete structure project management:

  • Structural design of the tower and the pavilion;
  • Realization of the business consultation documents for the structure part
  • Monitoring of works and approval of execution plans




All of the project’s structural plans are produced using a 3D model developed under Revit, a model integrating both new structures and retained existing structures:


Key information

Client: Aermont – SNC AER2

Assistant to the Client: ORFEO development

Architects: Jean-Paul Viguier and associates, Sisto Studios

Structures Project Management: setec tpi

Duration: 2017 – 2021


In a Nutshell

118mheight of the tower
6additional floorsadded to the tower
32 500m²tower floor area

Main Features :

Tower :

  • 5 levels of existing infrastructure
  • 27 existing levels of superstructures
  • 6 levels of added superstructures
  • height: 118m from the square
  • floor area: 32,500 m²


  • 8 levels of superstructure
  • height: 35m from the level between decks
  • floor area: 6,000 m²

The structural design, in terms of the redesign of the tower and the design of the new pavilion, achieves the initial objective of respecting the existing structures:

  • The extension of the tower is undertaken in composite slabs, reducing the loading over the existing bearing elements
  • The pavilion is executed as a steel frame over the existing parking that serves as its support

Whatever the case, the design of any new structures comprises the verification of the existing ones impacted in order to assess their compatibility.



The BIM approach: from REVIT to Pythagore
setec tpi designed the entire structure of the project with REVIT Structure, integrating the existing structures (existing tower and parking under the pavilion), in order to assess the addition of the new ones.

The REVIT 3D model is then exported to the in-house developed finite element calculation software Pythagore. This allowed for a significant time gain for the modelling of the tower and the pavilion.