To respond to Vinci Immobilier's call for tenders on block A1, general contractor Spie Batignolles Outarex, wishing to favor low-carbon precast concrete, called on the recognized know-how of Cibetec.
With a floor area of 4.305 m2, the A1 block, designed by the architecture firms Clément Vergely and Beal & Blanckaert, is made up of 10 apartment buildings articulated around an interior courtyard. In order to meet the strong environmental requirements of the operation, wood and low-carbon concrete are preferred, from the structure to the facades.
Having chosen to build these in architectonic concrete and concerned about the rendering of a project of this scale, Spie Batignolles Outarex has surrounded itself with the expertise of Cibetec.
"Beyond the recognized quality of finish of its prefabricated elements, Cibetec accompanied us during the costing and the design study but also by producing numerous samples to adapt their color to the architects' requirements, as well as a prototype » explains Karim Hasnaoui, Works Engineer at Spie Batignolles Outarex.
Cibetec thus intervened on:
- a mission to study and supply architectonic concrete elements,
- all the plinths of the block (excluding the Signal tower), from the ground floor to R+2, made of gray architectonic concrete with a smooth appearance on the interior courtyard side and sandblasted leather on the exterior facades. The lintels, strips and posts of different shapes depending on the building (with a 3 to 8 cm bevel) that make up the set are coated with an anti-graffiti protection,
- a 14-storey tower which has square posts on one side holding the balcony slabs. On the side without a balcony, trimmed triangular posts give relief to the facade. They are all in raw terracotta and red precast concrete, echoing the tone of the metal structure of the Signal tower. At the level of the balconies, there are added terracotta balustrades with specific grooves which required all the expertise of the prefabricator.
In total, more than 1.000 elements were made to measure in Cibetec's workshops from metal and wood molds specially developed for this operation, which represents nearly 1,4 km of poles, 770 lm of strips, 330 lm parapet railings, 252 m2 of balcony slabs, etc….
“Each product group had different geometric shapes, which multiplied the molds, the ways of manufacturing, and made it difficult to process the parts. Thanks to its experience, Cibetec has nevertheless succeeded in ensuring the homogeneity of the facades » concludes Joël Ferer, Manager of the Cibetec plant.