OSMANGAZI BRIDGEDEPARTMENTAL FIRE AND RESCUE SERVICEOSMANGAZI BRIDGE

Project details

Based in Rennes, the new SDIS (Departmental Fire and Rescue Service) of Ille-et-Vilaine is a 7800m² complex made up of a 170-meter long building , accompanied by a 30-meter high office tower.

Properties:
– Preventing decomposition for fresh concrete
– 3-4 hours of downtime
– Easy to pump
– Hydration control of deep foundations
– Resistance to bleeding of fresh concrete

CHRYSO expertise

The main feature of the new SDIS is the red-orange colour and the many openings that make it up. The central tower was cast on site, while the 450 prefabricated panels were specially designed to combine these visual characteristics with high mechanical constraints , such as resistance to seismic shocks.

Project technical challenges

The production of the 450 prefabricated panels, mostly in the 9 meter by 3 meter format, required a high level of expertise to meet these constraints. The outer skin of the panels, 8 cm thick and tinted throughout, had to prevent cracks during formwork removal while maintaining a very high quality finish.

The prefabricated panels, heavily reinforced to compensate for the large number of openings in the building’s façade, were designed for vibration-free casting and required the use of S5 class fluid concrete. The casting speed was not to exceed 85 cm per hour to obtain a homogeneous distribution of the concrete.

To ensure the red-orange tint, a specific process was put in place: The formwork bottoms were cleaned using a high-pressure, low-temperature gas to prevent scale deposits. Once the concrete facings were made, they were steamed to prevent traces of carbonation from the young concrete.

Project Participants

Project Owner: Ille-et-Vilaine department.

Project Management: LAN Architecture (agents).

Prefabricator: Soriba.

Engineering firm: Terrell (structure and fluid), Jean-Paul Lamoureux (acoustics), Bureau Michel Forgue (economist), Most (execution architect), Casso & Associés (SSI coordinator), Best (synthesis).
Company : Angevin (demolitions, foundations, earthworks, structural work).