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EUROPA
The height of the lantern could not exceed 58.20 m (upper limit imposed by
town planning regulations), and floor heights had to be adjusted to those of the
Résidence Palace
. A structure had to be designed that was able to include the
vertical and lateral stress of this stack of decks. At the time of the competition, the
beams were extremely thick, i.e., 3 metres. Fruitful reflection about the Polon-
ceau beams [see the works by Philippe Samyn, engineer, at the Vrije Universiteit
Brussel, and his book
Étude de la morphologie des structures à l’aide des indi-
cateurs de volume et de déplacement
,
Académie royale de Belgique, Classe des
sciences
, 2004] led to much more elegant morphological choices of great struc-
tural intelligence. The floor stress is taken over and supported by posts installed
on the lantern’s perimeter, thanks to metal ribs radiating from the centre of the
decks. The ceiling in the largest rooms show the substructure of these floors,
created by flat steel bars, interlaced and arranged from a central drum. Their areal
baskets evoke, as if mirrored and three-dimensional, the Michelangelo style or-
namental tiling of the
Campidoglio
. Georges Meurant’s ceilings offer a coloured
background to the interlaced lines of force, similar to metal basketwork; they
contribute to making perceivable the stress that drives the framework and al-
lows for the thinning of the floors; they provide an appeased vision of it. It is one
of the critical aspects of Philippe Samyn’s constructive philosophy: control over
a building’s soundness and securing it, forces to stiffen the system; architecture
must conserve flexibility. And yet, stiffness is achieved either by the quantity of
material or by geometry. The chosen solution consists in increasing the inher-
ent frequency of the floors, as strings in a musical instrument are tightened. The
link between the floors and the posts is the subject of articulation details, which
ensure their static and dynamic behaviour.
GLASS ELLIPSES
Image of the layout in the first basement of the lantern
destined to accommodate the main restaurant, 2013.
Ceiling by Georges Meurant.
