The enlargement of the MNCARS, designed by the prestigious architect Jean Nouvel in collaboration with Alberto Medem (winners of the restricted competition) is a symbolic work that will without doubt become a new step in the important urban transformation operation under way in the museum district of the Paseo del Prado in Madrid. Apart from its architectural singularity, the proposal is notable for its complex and open plan structure. The aerodynamic roof with enormous overhangs, reaching 36 m long starting from a depth of 3.40 m that progressively decreases until it almost disappears, apparently floats over the auditorium, the temporary exhibition rooms and the library. Supported on slim steel pillars with a free height of over 20 m that emerge from its roofs to rise 6 m above it, the building’s general roof covers almost 8,000 m2 in plan of the built-up site.
Without doubt the most notable feature is the isolated volume of the auditorium, with organic forms and clad externally with deep red polyester sheets. Structurally, it is supported on two concrete diaphragm walls of thickness varying between 1.15 and 0.85 m and 8 m long, partially pre-stressed, located eccentrically and in contact with the exterior floor structures in some parts only at certain levels. Powerful concrete beams 0.85 to 0.50 m thick and strongly reinforced and pre-stressed, emerge from these diaphragm walls as “outspread arms” curved in plan to carry the load of the auditorium located in front of the main diaphragm walls.
The structures of the temporary exhibitions building, 56 m x 24 m, and of the library, 62 x 90 m, are of steel porticos and composite decking.