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March 2015
Cement & Concrete
carbon neutral status
that removes carbon dioxide from
the ocean and binds it with calcium
oxide to form calcium carbonate or
coral around any concrete structures.
The growth achieved is about 5 cm a
weiler GmbH, Rheinstr. 40, 55435 Gau-Algesheim, Germany, Tel: +49 6725 9195 490, Fax: +49 6725 9195 491, info@weiler.net, www.weiler.net The PREMIUM SUPPLIER of the PRECAST CONCRETE INDUSTRY machines & equipments competent engineering high German quality modern technology individual solutions after sales service over 60 years experience worldwide acting TURNKEY PRECAST CONCRETE PLANTS Floors, walls, columns, girders, beams, stairs, piles, posts, lintels, … CONSULTATION, ENGINEERING & MACHINERY FORTHE PRECAST CONCRETE INDUSTRY weiler . 60 years made in Germany 1 9 5 4 - 2 0 1 4 BUILDEXPO NAIROBI KENIA 2-4 MAY 2015 BOOTH A111 TOTALLY CONCRETE JOHANNESBURG 11-13 MAY 2015 BOOTH 318 MEET US AT:year, whichworkswell toprotect such
structures against mechanical wave
action and corrosion.” Another focus
area is Advanced Re-Crystallisation
(ARC) technology, which refers to the
optimisation of the arrangement of
atoms and molecules in a solid and
amorphous state with concrete. “At
present Murray & Roberts is the only
construction company applying ARC
technology on a regular basis,” says
Attwell.
By using ARC technology we cross-
polymerise aggregate with the waste
binders used in geopolymer tech-
nology at room temperature while
absorbing carbon to formaprotective
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-engi-
neered silicate blend and a chemical
designmethodology that reduces the
activator requirement fromabout 200
litres per m³ to 20 litres per m³, as
used at the City Deep project.
“This reduces the normal shrink-
age experienced with geopolymer
technology from 1% to 0.025% and
reducing the requirement for heating
during curing,” concludes Attwell.
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