This document discusses the use of nanotechnology to improve the properties of concrete. It describes how the addition of nano-particles like carbon nanotubes, nano-silica, and polycarboxylates can enhance qualities such as strength, workability, and curing time. These nano-additives fill pores, improve bonding, and increase viscosity. Concrete mixed with such nanomaterials requires less water and curing time while achieving greater strength and durability. The document also reviews the properties and effects of specific nanomaterials used to reinforce concrete.

1. Prepared by
MRUTYUNJAY. S .HASARANI

2. • Nanotechnology is one of the most active
research areas which has wide applications
in almost all the fields.
• As concrete is most usable material in
construction industry it’s been required to
improve its quality.
• Improving concrete properties by addition
of nano particles have shown significant
improvement than conventional concrete.

3.  Improves the materials’ bulk properties.
 Ability to control or manipulate materials
at the atomic scale. NANOSCALE ATTACK ON ASR
(ALKALI SILICATE REACTION)
 To obtain thinner final products and faster
setting time.
 Cost effectiveness.
 Lowered levels of environmental
contamination.

4.  A concrete made with portland cement
particles that are less than 500nm as a
cementing agent.
 Currently cement particle sizes range from
a few nano-meters to a maximum of
about100 micro meters.

5.  Carbon Nanotubes.
 Nano-silica.
 Polycarboxylates.

6.  Carbon nanotubes are molecular-scale
tubes of graphitic carbon with outstanding
properties.
 They can be several millimetres in length
and can have one “layer” or wall (single
walled nanotube) or more than one wall
(multi walled nanotube).

9.  CNT are also highly flexible.
 Mechanically, CNT appear to be the
strongest material.
 The smaller diameters.
 Stiffest and strongest fibers.

10.  Is the first nano product that replaced the
micro silica.
 Advancement made by the study of
concrete at nano scale have proved nano
silica much better than silica used in
conventional concrete.

12.  High compressive strengths concretes
 High workability with reduced
water/cement ratio.
 Use of super plasticizing additives is
unnecessary.
 Fills up all the micro pores and micro
spaces.
 Cement saving upto 35-45%.

13.  Polycarboxylates or polymer based
concrete admixtures are High Range Water
Reducing admixture (HRWR).
 low dosage-reduce water as much as high
dosage of conventional admixtures.
 Higher dosage-produce Self Compacting
Concrete (SCC).
 This admixture type is very suitable for
underwater anti-washout concrete.

15.  Resistance to compression - 40 to 90MPa in
1 day.Resistance to compression from 70 a
100 MPa (or more) in 28 days.
 Produces high resistance even with low
addition (1 to 1.5 % of the cements weight)
and gives self compacting characteristics
with higher proportions (2.5 %).

16.  Meets the norms of environmental
protection.
 70% less use of additives as traditional
silica, super plasticizers or traditional
fibres.

17.  Cessation of contamination caused by
micro silica solid particles.
 Lower cost per building site.
 Concrete with high initial and final
compressive and tensile strengths.
 Concrete with good workability.

18.  Well dispersed nano particles increase the
viscosity of the liquid phase, improves the
segregation resistance and workability of
the system.
 Accelerates the hydration.
 Better bond between aggregates and
cement paste.
 Improves the toughness,shear,tensile
strength and flexural strength of concrete.

19.  If Portland cement can be formulated with
nano-size cement particles, it will open up a
large number of opportunities.
 The cement will not only be more
economical than organic polymers but also
will be fire resistant.
 A number of investigations have been
carried out for developing smart concrete
using carbon fibers.

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Opportunities and Challenges.” Proceedings of the International Conference
application of Technology in Concrete Design.
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Hill,
New York, 1992, 530 pp.
[4] “Concrete”, Wikipedia, http://en.wikipedia.org/wiki/Concrete.
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and
composites.” Applied Mechanics Review, 56, 2003, 215-230.
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Cement and Concrete Research. 34. 2004. P. 1043 – 1049.
[7] McCARTHY, M.J. & DHIR, R.K. Development of high volume fly ash cement.