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CONSTRUCTION WORLD
APRIL
2015
CEMENT AND CONCRETE TECHNOLOGY
The pan mixer at
the Concrete Centre
of Excellence, which
aims to raise the
level of construction
technology within
the Murray & Roberts
Group.
used in geopolymer technology
at room temperature while
absorbing carbon to form a
protective membrane due to
the surface tension chemistry
reducing the shrinkage and
causing a curing membrane which
forms automatically.
“The particular difference
in the South African context is a
re-engineered silicate blend and
a chemical design methodology
that reduces the activator require-
ment from about 200 litres per m³
to 20 litres per m³, as used at the
City Deep project, while reducing
the normal shrinkage experienced
with geopolymer technology from
1% to 0,025% and reducing the
requirement for heating during
curing,” Attwell concludes.
The cube tester at the Concrete Centre of Excellence.
The curing baths at the
Concrete Centre of Excellence.
The drying oven at the Concrete
Centre of Excellence.