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CONSTRUCTION WORLD
NOVEMBER
2015
PROJECT PROFILE
LSFB category commendation: Kuruman
Casino Façade
The judges commented that local architects and engineers have
in the last few years recognised the insulating values and architec-
tural flexibility offered by the Light Steel Frame Building (LSFB) and
External Thermal Insulation Composite System (ETICS) systems.
The 300 m² Kuruman Casino facade is supported on a light steel
framed structure which was factory built. Sheathing comprising OSB
board was fixed to the frame and covered by a vapour permeable
membrane which was in turn fixed to the sheathing, followed by EPS
insulation boards. The EPS board was then primed and sealed with a
decorative acrylic resin topcoat. The external insulation results in a
‘warm frame’ which prevents condensation on the steel frame adding
to the durability of the structure.
Winner – mining and industrial category: Medupi
Power Station-Air Cooled Condenser
In 2007, GEA approached A. Leita and Kentz to submit a bid for the Medupi air
cooling structures, some 26 000 tons of steel. Leita teamed up with Cadcon
and Boksan Projects and formed the ABC Joint Venture with Leita leading the
fabrication team with Kentz doing the on-site work.
According to the judges, when one visits the site, because of the enormous
boiler houses which stand close to the air cooling units, one is surprised to
learn that each unit has over 4 000 tons of steelwork. “To grasp just how big a
project the air cooling actually is, it was necessary for us to drill down into what
makes these units tick,” they said. There is an air cooling unit for each of the six
boilers; the radiators sit on a structural steel support structure; floor beams are
covered with 4 mm floor plates; an A-frame structure is fabricated out of heavy
H beams; and the fan bridges span between the main girders.
Winner – architectural category:
Multichoice City
Multichoice City is a large expansion to the east
of the current Multichoice/MNET campus on the
eastern side of Bram Fischer Drive in Randburg. The
primary purpose of the building is for offices and a
call centre but the building has been developed as
the flagship to the current campus.
A visitor entering the building is immediately
greeted by a grand volumetric atrium space with a
wonderfully elegant tubular strutted arch structure
supporting air inflated ETFE cushion cladding. The
strutted arch spans 24 metres and its form is ideal
for resisting the more dominant uplift wind forces of
such a structure, whilst being quite slender in form
as a result of the very light (in mass) ETFE cushions.
The atrium space is further complemented by beau-
tifully detailed structural steel staircases.
Structurally the roof comprises fabricated box
girders tapered in section cantilevering generally
12 metres (maximum cantilever being 13,5 metres).
The closed box form is further stabilised by a
tubular bracing network ensuring, despite the large
cantilever, that the structure remains stable. The
back edge of the roof allows free flow of wind under
it to ensure wind uplift forces are minimised.
2015 WINNERS
STEEL AWARDS