sections, consisting of three beams and one node
and bolting these to the partly installed skylight. A
series of shoring towers were erected at specific
locations to provide temporary support while the
structure was being installed. Once a full arch
section had been installed and fully torqued, the
shoring towers were removed.
ETFE
The cladding consists of a series of ethylene
tetra-flouro-ethylene (ETFE) air-filled pillows.
Each pillow is supported by aluminium extrusions
and the system is inflated by three air machines
Mall of Africa
mounted on the roof. Each air machine is
equipped with two blowers a dehumidifier and
a series of sensors which continually monitor
the overall pressure in the pillows and adjust this
pressure as required. Based on glare and shading
studies, the pillows were made of a combination
of either two partly opaque ETFE layers or one
clear printed ETFE upper layer and a fully clear
lower layer.
The extrusions and ETFE cladding were
installed using nets which were tied to the steel
structure and removed once a portion was fully
installed and water-tested.
39