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Nano Research & Applications
ISSN 2471-9838
Advanced Nano 2017
Page 77
September 11-12, 2017 Amsterdam, Netherlands
20
th
International Conference on
Advanced Nanotechnology
Nanotechnology and concrete construction
Surendra P Shah and Walter P Murphy
Northwestern University, USA
S
uper tall buildings such as one kilometer high
Kingdom Tower are constructed with concrete as
a structural material. Such tall buildings are made with
so called high performance concrete, which can have
strength 5 times that of conventional concrete. The
development of high strength concrete is a result of
our understanding of particle packing, rheology and
microstructure engineering. Concrete is a critical material
for infrastructure; the world wide consumption of concrete
is about 2 tons for every living human being. However,
its continuing use will require improving its sustainability.
Nanotechnology is playing an increasing role in making
concrete more sustainable. Some examples are given.
One approach to making concrete more sustainable is to
replace Portland cement (and its significant carbon foot
print) with fly ash, a waste material from burning coal.
When fly ash is replaced with Portland cement, the rate of
strength development slows down which is not desirable.
Addition of Nano particle such as Nano silica accelerates
the chemical reaction by providing nucleation sites .In
addition, characterization of Nano structure of calcium
silicate hydrate by Nano indentation, AFM, FTIR and NMR
shows beneficial Nano scale modification. Concrete is a
brittle material, prone to cracking. Concrete structures are
reinforced by see bars at a millimetre scale. However,
flaws in cement paste are in Nano scale. To reinforce
concrete at Nano scale addition of carbon Nano tube
is studied. The key challenges include dispersion and
rheology. Recent studies have demonstrated that adding
a very small amount (0.05%) of well dispersed CNT has
a profound effect on performance: mechanical properties,
piezo-resistivity, transport properties as well as corrosion
reinforcing steel. Such multi functionality is probably
related to altered Nano structure of concrete.
s-shah@northwestern.eduNano Research & Applications