Major Structures

La Seine Musicale: architectural feats, innovative solutions and professional collaborations

Credits: Laurent Blossier.

La Seine Musicale opened its doors in April 2017 in the heart of Jean Nouvel’s urban design, at the tip of Seguin Island in Boulogne-Billancourt, next to Paris. Designed by architect Shigeru Ban in collaboration with Jean de Gastines, this cultural venue consists of an auditorium and modular performance hall for concerts and public events. During the design phase of the unique architecture, the CSTB helped stakeholders meet their technical challenges. Aerodynamics experts performed wind loading studies for the building and solar sail, and advisors assessed the green roof and glass facade.

    With 35,000 m2 of surface area, La Seine Musicale boasts several architectural achievements:
  • Large sail-shaped structure with solar panels that follows the sun’s path
  • Green roof constructed on a steep incline, a green space for visitors and a refuge for biodiversity
  • Glass facade measuring 4000 m2 and ovoid shaped

Wind loading for the mobile solar sail

The consulting firm RFR (Artelia), commissioned by Bouygues Construction, called on the expertise of the CSTB for tailored aerodynamics studies.

1st stage: Characterize the aerodynamic environment of La Seine Musicale. Using local weather and topographic data, the CSTB performed computational fluid dynamics (CFD) simulation to determine the wind speeds on the site for all incidences. The measurements were fine-tuned in wind tunnels using a 1:500 scale model of the site and incorporating the effects of nearby buildings.

2nd stage: Optimize wind loading for the solar sail through an experimental campaign (tests on 1:250 and 1:75 models in a wind tunnel). The CSTB initially tested the mobile solar sail in several positions. It also considered the impact of the current environment and that envisaged by Jean Nouvel. Subsequently, it measured the local and overall wind forces on the solar panels (1000 m²) and supporting structure to optimize the wind load on the sail.

Making the steep green roof safe

Its slopes incline at 76% and yet the roof of La Seine Musicale has a public garden and offers a biodiversity haven. This innovation fundamentally changed the world of green building norms.

    The CSTB supported the company AMC Etanchéité in assessing this green roof with exceptional slopes. The assessment focused on the design of the structures:
  • Insulation and protection of the garden: The supporting structure includes retaining abutments (composite reinforced concrete slabs).
  • Waterproofing: Metal gabions provide compartmentalization and keep the soil and plant cover in place.

In 2015, the multidisciplinary expert committee—construction, landscape, horticulture—issued a favorable Technical Experimentation Assessment (ATEx), with recommendations (installation method, performance testing, access and security conditions, maintenance requirements).

Assessing a glass facade in an inclined timber frame

The La Seine Musicale auditorium is nestled in the middle of an egg made of woven wood, with rounded shapes covered with a glass skin. The CSTB was approached by the company M Tech to assess its innovative system for a glass roof and tilting facade (+15°) made of insulated glazing units.

Meetings to prepare for an ATEx focused on the installation conditions for glazing on nonplanar timber framing. Based on comparative calculations, the CSTB defined the test protocols (water and air tightness, wind resistance, impact strength, safety of people).

During actual assessment, the results of the tests made it possible to check the cold stability and durability of the structure. In addition, its feasibility was assessed by producing a prototype on-site and installing the first glazing infilling.

A favorable ATEx was issued to M Tech for its solution in 2016.