RATP Bus Center in Thiais / ECDM

Architects: Emmanuel Combarel Dominique Marrec
Location: Thiais, France
Engineering: BETOM – SIT
Main Contractor: DUTHEIL – BETSINOR / LABASETERE
Client: PARIS HABITAT
Program: Administrative building
Project year: 2003-2007
Site Area: 3,5 há
Constructed Area: 2,450 sqm
Photographs: Benoit Fougeirol – Philippe Ruault

Located in the southern suburban area of Paris along wide boulevards and roadway interchanges, in an industrial landscape characterised by a succession of boxes (at best basic), the RATP Bus Centre in Thiais controls all the bus lines of the south and east of Paris.

The centre accommodates 300 buses. 800 bus drivers pass through the building every day, including the administrative, the security and the maintenance staffs which manage the Bus Centre. It’s a flux building.

In this fuzzy territory, only one federating element can be pointed out: the 100 % inorganic ground of the site – a mix of asphalt and concrete.

So, we reduced the site to its primary function: a bus park, a vast monolithic slab, uniform mineral territory.

The existing concrete crust that covers the evolution area of the buses is distorted, modeled to cover the administrative center. The building starts with the deformation of the ground and continues it with an apparently similar material, a sheet of ultra high performance concrete, paradoxical and superlative, 3 cm thick displaying a non slippery texture of dots in relief like a game of “LEGO” (24 mm diameter  x 7 mm high, distant  of 12 mm) contributing to a kinetic morphing which responds to very sophisticated demands : informality of the structure, constant evolution of the plans, density, homogeneity, dematerialization, precision, durability towards emphasized constraints. It ensures a continuity of the ground from the road, to the skin of the façades, the suspended ceilings and the terrace rooftop without any rupture, proposing a merging between the building and its support to a point of confusion. The building has neither a beginning nor an end.

The plasticity of the material combined with its mechanical performance induces an “All-over” appropriate to a multiplicity of uses and maximized solicitations, possibly opened to a non-control of the limits and the uses.

The building appears like a monolith with rounded edges, polished somehow, required here as a morphing of the context to cover the carcass of a composite program. The result is a dense, inert and deaf building, as enigmatic as “the hull of a Russian submarine in the waters of Murmansk”.

The concrete hull is cut out with a Stanley knife, surgical incisions revealing cavities of reflective and coloured glass. Treated with silver mirror dots, chromatics of the glass products are inspired by the tinted curtain wall frontages of the “office” buildings which border the main road.

Aside the administrative building, the program also includes the realization of a new checkpoint of the centre and a bikes shelter.