concrete which has enabled the study of chloride diffusion in concrete (which causes corrosion of reinforcement). Concrete is, after all, a macro-material strongly influenced by its nano-properties and understanding it at this new level is yielding new avenues for improvement of strength, durability and monitoring. nanotechnology in concrete materials nano cement nanotechnology review applications of concrete hydraulic cement in caulking tubes quikrete msds sheets ingram readymix nano concrete sealer interesting civil engineering topics civil engineering topics for presentation civil seminar topics ppt civil engineering seminar topics 2018 seminar topics pdf best seminar topics for civil engineering seminar topics for mechanical engineers latest civil engineering seminar topics

1. Nano
Concrete
AGLAIA

2. INTRODUCTION
• The nanotechnology generated products have unique
characteristics, and can significantly fix current construction
problems, and may change the requirement and organisation
of construction process.
• The recent developments in the study and manipulation of
materials and processes at the nanoscale offer the great
prospect of producing new macro materials, properties and
products.
• But till date, nanotechnology applications and advances in
the construction and building materials fields have been
uneven.
• Exploitation of nanotechnology in concrete on a commercial
scale remains limited with few results successfully converted
into marketable products.

3. •The main advances have been in the nanoscience of cementitious materials
with an increase in the knowledge and understanding of basic phenomena in
cement at the nanoscale.
•Concrete, the most ubiquitous material in the world, is a nanostructured,
multi-phase, composite material that ages over time.
•It is composed of an amorphous phase, nanometer to micrometer size
crystals, and bound water.
• The amorphous phase, calcium–silicate–hydrate (C–S–H) is the ‘‘glue”
that holds concrete together and is itself a nanomaterial.
•Viewed from the bottom-up, concrete at the nanoscale is a composite of
molecular assemblages, surfaces (aggregates, fibres), and chemical bonds
that interact through local chemical reactions, intermolecular forces, and
intraphase diffusion.
•Properties characterizing this scale are molecular structure; surface
functional groups; and bond length, strength (energy), and density.

4. • The structure of the amorphous and crystalline phases and of
the interphase boundaries originates from this scale.
• The properties and processes at the nanoscale define the
interactions that occur between particles and phases at the
microscale and the effects of working loads and the
surrounding environment at the macroscale.
• Processes occurring at the nanoscale ultimately affect the
engineering properties and performance of the bulk material.
• There are two main avenues of applications of
nanotechnology in concrete research;the nanoscience and
nano-engineering.
• Nanoscience deals with the measurement and
characterization of the nano and microscale structure of
cement-based materials to better understand how this
structure affects macro scale properties and performance
through the use of advanced characterization techniques and
atomistic or molecular level modeling.

5. • Nano-engineering encompasses the techniques of
manipulation of the structure at the nanometer scale to
develop a new generation of tailored, multifunctional,
cementitious composites with superior mechanical
performance and durability potentially having a range of
novel properties such as: low electrical resistivity, self-
sensing capabilities, self-cleaning, self-healing, high
ductility, and self-control of cracks.
• Concrete can be nano-engineered by the incorporation of
nanosized building blocks or objects (e.g., nanoparticles
and nanotubes) to control material behavior and add novel
properties, or by the grafting of molecules onto cement
particles, cement phases, aggregates, and additives
(including nanosized additives) to provide surface
functionality, which can be adjusted to promote specific
interfacial interactions.

6. • At the basic science level, much analysis of concrete is being done
at the nano-level in order to understand its structure using the
various techniques developed for study at that scale such as Atomic
Force Microscopy (AFM), Scanning Electron Microscopy (SEM)
and Focused Ion Beam (FIB).
• This has come about as a side benefit of the development of these
instruments to study the nanoscale in general, but the understanding
of the structure and behaviour of concrete at the fundamental level
is an important and very appropriate use of nanotechnology.
• One of the fundamental aspects of nanotechnology is its
interdisciplinary nature and there has already been cross over
research between the mechanical modeling of bones for medical
engineering to that of concrete which has enabled the study of
chloride diffusion in concrete.
• Concrete is, after all, a macro-material strongly influenced by its
nano-properties and understanding it at this new level is yielding
new avenues for improvement of strength, durability and
monitoring.

7. Addition of nanosized and
nano-structured materials
• Nanosized particles have a high surface area to volume ratio,
providing the potential for tremendous chemical reactivity.
Much of the work to date with nanoparticles has been with nano-
silica (nano-SiO2) and nano-titanium oxide (nano-TiO2) .
• There are a few studies on incorporating nano-iron (nano-
Fe2O3), nano-alumina (nano-Al2O3) , and nanoclay particles .
Additionally, a limited number of investigations are dealing with
the manufacture of nanosized cement particles and the
development of nanobinders .
• Nanoparticles can act as nuclei for cement phases, further
promoting cement hydration due to their high reactivity, as
nanoreinforcement, and as filler, densifying the microstructure
and the ITZ, thereby, leading to a reduced porosity.

8. • The most significant issue for all nanoparticles is that of
effective dispersion.
• Though it is particularly significant at high loadings, even
low loadings experience problems with self-aggregation,
which reduces the benefits of their small size and creates un-
reacted pockets leading to a potential for concentration of
stresses in the material.

9. • Nano-SiO2 has been found to improve concrete workability and
strength, to increase resistance to water penetration, and to help
control the leaching of calcium, which is closely associated with
various types of concrete degradation.
• Nano-SiO2, additionally, was shown to accelerate the hydration
reactions of both C3S and an ash–cement mortar as a result of
the large and highly reactive surface of the nano particles.
• Nano-SiO2 was found to be more efficient in enhancing strength
than silica fume.
• Addition of 10% nano-SiO2 with dispersing agents was
observed to increase the compressive strength of cement mortars
at 28 days by as much as 26%, compared to only a 10% increase
with the addition of 15% silica fume.
• Even the addition of small amounts (0.25%) of nano-SiO2 was
observed to increase the strength, improving the 28 day
compressive strength by 10% and flexural strength by 25%.

10. •It was noted that the results obtained depended on the production route
and conditions of synthesis of the nano-SiO2 (e.g., molar ratios of the
reagents, type of reaction media, and duration of the reaction for the sol–
gel method) and that dispersion of the nano-SiO2 in the paste plays an
important role.
•Nano-SiO2 not only behaved as a filler to improve the microstructure
but also as an activator to promote pozzolanic reactions .

11. • Nano-TiO2 has proven very effective for the self-cleaning of
concrete and provides the additional benefit of helping to
clean the environment.
• Nano-TiO2 containing concrete acts by triggering a
photocatalytic degradation of pollutants, such as NOx,
carbon monoxide, VOCs, chlorophenols, and aldehydes from
vehicle and industrial emissions.
• ‘‘Self-cleaning” and ‘‘de-polluting” concrete products are
already being produced by several companies for use in the
facades of buildings (e.g., the Jubilee Church in Rome, Italy).
• In addition to imparting self-cleaning properties, a few
studies have shown that nano-TiO2 can accelerate the early-
age hydration of Portland cement, improve compressive and
flexural strengths, and enhance the abrasion resistance of
concrete.
• However, it was also found that aging due to carbonation
may result in loss in catalytic efficiency

12. APPLICATION OF NANOTECHNOLOGY IN
CONSTRUCTION
• Application in concrete:
• Addition of nano scale materials into cement could improve
its performance.
• Use of nano-SiO2 could significantly increase the
compressive for concrete, containing large volume fly ash, at
early age and improve pore size distribution by filling the
pores between large fly ash and cement particles at nano
scale.
• The dispersion/slurry of amorphous nano silica is used to
improve segregation resistance for self-compacting concrete.
• It has also been reported that adding small amount of carbon
nanotube (1%) by weight could increase both compressive
and flexural strength.

13. • Application in Steel
• The new steel was developed with higher corrosion-
resistance and weld ability by incorporating copper nano
particles from at the steel grain boundaries.
• Coating
• The coatings incorporating certain nano particles or nano
layers have been developed for certain purpose.
• It is one of the major applications of nanotechnology in
construction.

14. • Nanosensors
• They have been developed and used in construction to monitor
and/or control the environment condition and the
materials/structure performance.
• One advantage of these sensors is their dimension (10 -9m to 10-
5m).
• These sensors could be embedded into the structure during the
construction process.
• The sensors can be used to monitor concrete corrosion and
cracking.
• The smart aggregate can also be used for structure health
monitoring.
• The disclosed system can monitor internal stresses, cracks and
other physical forces in the structures during the structures’ life. It
is capable of providing an early indication of the health of the
structure before a failure of the structure can occur.

15. CONCLUSION
• Nanotechnology offers the possibility of great advances
whereas conventional approaches, at best, offer only
incremental improvements in the field of construction
engineering.
• It is not exactly a new technology, rather it is an
extrapolation of current ones to a new scale and at that scale
the conventional tools and rules no longer apply.
• It is the opposite of the traditional top-down process of
construction, or indeed any production technique, and it
offers the ability to work from the “bottom” of materials
design to the “top” of the built environment.
• many of the advances offered by nanotechnology, be they for
economic or technical reasons, are years away from practical
application, especially in the conservative and fragmented
construction business.

16. • The main limitation is the high costs of nanotechnology, also
concerns with the environmental and health effects.
• The waves of change being propagated by progress at the nano
scale will therefore be felt far and wide and nowhere more so than
in construction due its large economic and social presence.
• There are three main issues that are preventing the widespread
use of the nanotechnology
(1) Lack of vision to identify those aspects that could be changed
through its use.
(2) Lack of skilled personnel
(3) Level of investment.

17. • The potential of nanotechnology to improve the performance
of concrete and to lead to the development of novel,
sustainable, advanced cement based composites with unique
mechanical, thermal, and electrical properties is promising
and many new opportunities are expected to arise in the
coming years.
• However, current challenges need to be solved before the
full potential of nanotechnology can be realized in concrete
applications, including proper dispersion; compatibility of
the nanomaterials in cement; processing, manufacturing,
safety, and handling issues; scale-up; and cost.

18. REFERENCES
• Tina Lai "Structural behavior of Nano Concrete and their
applications to lightweight bridge decks" ,M.Tech thesis,
MIT, 2009.
• Sergiu Cal in, Ciprian Asavoaie and N. Florea, "Issues for
achieving an experimental model" Bul. Inst. Polit. lai, t. LV
(LIX), f. 3, 2009.
• Martina Schnellenbach-Held and Karsten Pfeffer,"Punching
behavior of biaxial hollow slabs" Cement and Concrete
Composites, Volume 24, Issue 6, Pages 551-556, December
2002.
• Sergiu Calin, Roxana Glntu and Gabriela Dascalu,
"Summary of tests and studies done abroad on the Nano
Concrete system", The Buletinul Institutului Politehnic din
la, t. LV (LIX), f. 3, 2009.

19. Thank you
For more…. aglaiaconnect2018@gmail.com