nanotechnology in building construction materials

NANOTECHNOLOGY

IN BUILDING CONSTRUCTION MATERIAL

By: GAURAV JAIN

B-TECH (Final yr.)

CONTENTS

• Introduction

• What nanotechnology is?

• Introduction to Nanomaterials

• Application of Nanotechnology

• Barriers

• Conclusion

INTRODUCTION

• We are very familiar with the concept of getting raw materials,

bringing them together in an organized way and then putting them

together into a recognizable form.

• This is our role in society and we have performed it well for hundreds

or thousands of years. So we can say construction is definitely not a

new science or technology and yet it has undergone great changes

over its history.

• In the same vein, nanotechnology is not a new science and it is not a

new technology either. It is rather an extension of the sciences and

technologies that have already been in development for many years

What is Nanotechnology ?

• Nanotechnology is the use of very small pieces of material by

themselves or their manipulation to create new large scale

materials.

• At the Nano-scale material properties are altered from that of larger

scales.

• The Nano-scale is the size range from approximately 1nm to

100nm.

• Nanotechnology is an enabling technology that allows us to develop

materials with improved or totally new properties.

Introduction to Nano-materials

Nano-particles:-

• It is defined as a particle with at

least one dimension less than

200nm. Nano-particles made of

semiconducting material(Ex-

Silicon)

Nano-composites:-

• It is produced by adding Nano-

particle to bulk material in order to

improve its bulk properties

Carbon Nano-tubes:-

• They are the form of carbon that was

first discovered in 1952 in Russia and

then re-discovered in the 1990’s in

Japan.

• They are cylindrical in shape with

Nano-meter diameter.

• Production cost of Nano-tubes is

high and the price ranges from 20€

to 1000€ per gram depending on

quality.

• Types of Nano-tubes:-

Single-walled carbon Nano-tubes

Multi-walled carbon Nano-tubes

Titanium Dioxide (TiO2)

• Titanium dioxide is a widely used white pigment.

• It can also oxidize oxygen or organic materials, therefore, it is

added to paints, cements, windows, tiles etc.

• As TiO2 is exposed to UV light, it becomes increasingly

hydrophilic (attractive to water), thus it can be used for anti-

fogging coatings or self cleaning windows.

Applications of Nano-technology

Nanotechnology is widely used in construction material as:

• In Concrete

• In Steel

• In Wood

• In Glass

• In Coating

• In photovoltaic

Nanotechnology in concrete

Concrete:- It is a mixture of cement, sand

coarse aggregate and water, The mechanical

behavior of concrete material depends on the

phenomenon that occurs on a micro and Nano

scale.

Nanotechnology can modify the structure of

concrete material and finally improves in

properties of materials as-

• Bulk density

• Mechanical performance

• Volume stability

• Durability

• Sustainability of concrete

• Exploring and modifying these Nano

scale pores can result in improved

concrete

• These addition could compensate for

its weakness in tension and result in

concrete with greatly improved

stress-strain behavior

• The addition of Nano scale silica fume

operates at a Nano scale and can

improve durability of concrete

structures exposed to de-icing salts.


CNT in CONCRETE:-

• The addition of small amount (1%) of CNT improves the

mechanical property of concrete

• Oxidized MWNTs shows the best improvements in both

compressive(+25N/mm2) and flexural

strength(+8N/mm2).

Research into haematite (Fe2O3) nanoparticles added

to concrete has shown that they also increase strength

as well as offering the benefit of monitoring stress

levels through the measurement of section electrical

resistance.


Nanotechnology in Steel

Need of nanotechnology in steel:-

• Fatigue is a significant issue that can lead to

the structural failure of steel subject to cyclic

loading, such as in bridges or towers.

• Stress risers are responsible for initiating

cracks from which fatigue failure results.

• Addition of copper nanoparticles reduces

the surface unevenness of steel which then

limits the number of stress risers

Temperature restriction:-

• Above 750 F, steel starts to loose

its structural integrity, and at 1000

F, steel loses 50 % of its strength

• Infusion of steel with Nano scale

copper particles could maintain

structural integrity up to 1000 F

• New infused steel allows ultra high

strength, corrosion resistance and

have good surface finish.


High strength steel cables:-

• Current research into refinement of cementite

phase of steel to a Nano size has produced

stronger cables

• A stronger cable material reduce the costs and

period of construction, especially in bridges

• Sustainability is also enhanced by the use of

higher cable strength as this leads to a more

efficient use of material

• High rise structures require high strength joints

and this leads to the need of high strength bolts.



Bolted connection:-

• The capacity of high strength bolts is realized

generally through quenching and tempering

• Vanadium and molybdenum nanoparticles

delays the problems associated with high

strength bolts and also improving the steel’s

micro- structure

Welding connection:-

• The addition of nanoparticles of magnesium

and calcium makes the HAZ(Heat Affected

Zone) grains finer in plate steel and this leads

to an increase in weld toughness.

CONNECTIONS

BOLTED

WELDED

There are two international product:-

• Sandvik Nanoflex has both the desirable qualities of a high Young’s

Modulus and high strength and it is also resistant to corrosion due to

the presence of very hard nanometer-sized particles in the steel

matrix.

• MMFX2 steel, while having the mechanical properties of

conventional steel, has a modified Nano-structure that makes it

corrosion resistant and it is an alternative to conventional stainless

steel, but at a lower cost.


Nanotechnology in Wood

• Wood is also composed of nanotubes

or “Nano fibrils”; namely,

lignocellulose (woody tissue)

elements which are twice as strong as

steel.

• Researchers have developed a highly

water repellent coating based on the

actions of the lotus leaf as a result of

the incorporation of silica and alumina

nanoparticles and hydrophobic

polymers.

Nanotechnology in Glass

• Most of the glass used on the exterior

surface of buildings to control light and heat

in order to control the building environment

and contribute to sustainability.

• Titanium dioxide (TiO2) is used as

nanoparticle form to coat glazing since it

has sterilizing and anti-fouling properties.

conventional glass

self-cleaningglass

Self cleaning of Glass

• Glass incorporating this self cleaning

technology is available on the market

today.

• Fire-protective glass is another

application of nanotechnology. This is

achieved by using a layer sandwiched

between glass panels (an interlayer)

formed of fumed silica (SiO2)

nanoparticles which turns into a rigid

and opaque fire shield when heated.

Nanotechnology in Glass

Nanotechnology in Coatings

• Coating is an area of significant research

in nanotechnology

• Nanotechnology is being applied to

paints and insulating properties,

produced by the addition of Nano-sized

cells, pores and particles.

• The TiO2 will break down and

disintegrate organic dirt through

powerful catalytic reaction.

• This research opens up the intriguing

possibility of putting roads to good

environmental use.

Nanotechnology in Fire-Resistance

• This is achieved by the mixing of

carbon nanotubes with the

cementious material to fabricate

fibre composites that can inherit

some of the outstanding properties

• Polypropylene fibres are also being

considered as a material for

increasing fire resistance and this is a

cheaper option than conventional

insulation.

Nanotechnology in Photovoltaic

• Predominant photovoltaic

material is silicon, but an

emerging technology involves

the use of dye-sensitized nano-

TiO2.

• Large surface area of Nano

TiO2 greatly increases

photovoltaic efficiency.

• Also has potential for lower

material and processing costs

relative to conventional solar

cells.

Barriers

Regulatory, legal, political and ethical issues.

Competition with established micro scale technologies.

License of proof-of-concept Nano tools, and delivery

system.

Safety and toxicity.

Implementation cost of plant.

Barriers cont…

• 1. FABRICATION

Current efforts in the field of nanotechnology are focussed on the fabrication,

characterization and use of these materials on a Nano scale.

• 2. HEALTH

Nanotechnology based construction products might be harmful to health. example, the

nanotubes might cause lung problems to the workers.

1. FABRICATION

2. HEALTH

3. ENVIRONMENT

4. COST

• 3. ENVIRONMENT

The effect of various nanomaterials on the natural environment is hotly

debated in nanotechnology and environmental research.

Moreover it will create a new category of Nano-waste which has to be

extracted and treated.

• 4. COST

The cost of most nanotechnology materials and equipment are relatively

high. In comparison to traditional method.

It’s a challenge for construction engineer to provide a facility to the general

public at a reasonable cost.

Barriers cont..

Real life Examples…

• Building made by using

self-cleaning concrete

(Church ‘‘Dives in

Misericordia”, Rome, Italy)

• TiO2 coating on roads for

pollution reduction

Nano house , Australia:-

University of Technology ,Sydney

(UTS) have developed a model

house that shows how new

materials, products and processes

that are emerging from

nanotechnology research and

development might be applied to

our living environment.

Real life Examples…

CONCLUSION

• Present day we are in great search for alternate

materials this can effectively be achieved through

the emerging field of Nanotechnology.

• Nanotechnology is not exactly a new technology,

rather it is an extrapolation of current ones to a

new scale.

• The main limitation is the high costs of

nanotechnology, also concerns with the

environmental and health effects.

• There is wide scope of research for application of

nanotechnology in the building industry and it

shall help in conserving the material resources.

References

Journals.iop.org

Nanoarchitecture.net

Nanoforum.org

Wikipedia.org

references

nanotechnology in building construction materials

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