Nanosilica in construction materials - KIVI in construction materials ... Cement Fly ash Powders Natural sand Coarse ... Pyrogenic (silica fume slurry) Pyrogenic

11/22/2011

Nanosilicain construction materials

KIVI NIRIA Congress, November 23th, 2011

Delft, The Netherlands

G. Quercia Bianchi

M2i PhD research staff

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Copyrights ® M2i 2011

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• Turnover 11 billions Euros

• 5000 companies

• 84000 employees

Dutch Civil industry

Source: M2i progress report (2010), www.google.com


Sustainable use of raw materials

•Material↓ � quality↑

•Use recyclable materials

•Environmental impact ↓

Economy

Environment

Society

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Ceramics

Metals

Polymers

Naturals

Concrete

Floor tiles

Masonry

Glass

Steel

Aluminium

Iron

Wood

Polyurethane

Polystyrene

PVC

Stones

Construction materials

CompositesFiber R.

Asphalt

Particle R.

Mortar

Grout

Plasters

HPC

SCC

VC

Gypsum

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1 ton concrete ≈ 0.11 ton cement

1600 Mton cement ≈ 1.65 Gton CO2 ↑

Global productions of construction

Materials (2008)

Source: Brouwers (2008)

(700)

(350)

(1750)(46000)

Energy consumed

(kWh/m3)

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Most used manmade material (in volume).

Water + Cement

(matrix)

Coarse aggregate

Fine aggregateAir

Admixtures

CementCement production is

responsible for

5 to 8% CO2 worldwide

emissions

Concrete

Source: www.google.com


Raw materials

• Limestone (CaCO3, MgCO3)

• Clays (SiO2, Al2O3, Fe2O3, MgO, etc)

• Sand (SiO2)

• Iron ores (Fe2O3)

Cement CO2 footprint

Source: PCA (2005)

1 ton cement ≈ 1 ton CO2 ↑

Source: www.google.com

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Source: Based on Sobolev, Ferrara and Ye works

Concrete raw materials

5µm to 46mm

0.4µm to 36mm

0.05 µm to 36mm

4 decades

7 decades!TU/e mix tool

Nano-SiO2

Precipitated

Silica

Micro silica

Fines

minerals

Metakaolin Portland

Cement

Fly ash

PowdersNatural

sand

Coarse

aggregates


The main hydration

products is the C-S-H

gel and its the mayor

responsible for the

concrete mechanical

properties.

C-S-H is a nano-

structured material,

thus its study, control

and modifications can

lead to tailored made

properties.

Atomic scale

20X20 nm

1,1 nm

C-S-H in

Poros

C-S-H

C-H Cement

C-S-H out

C-S-H in

C-S-H out

Sources: Guang, Ye (2003), Jennings (2001), Ulmen (2008), Beaudoin, J (1999).

Why Nanotechnology?

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Nano-SiO2?: powder or colloidal suspension.

Nanometer sized particles (2 to 400 nm).

Source: Graces Co. (2009) and www.google.com

What is nano-silica?

Irregular/Spherical

SiO2 amorphous

particlesNano(colloidal) SiO2SiO2


Nowadays techniques

•Sol-gel process•Vaporization of silica•Biological method•Precipitation method

New technique (route)

•Olivine (mine or waste) + H2SO4 = nS (6 to 30 nm).

“State-of-the-art” (production nS)

€€

Production routes of nano-silica

(Mg, Fe)2SiO4

TU/e parallel

project

Source: Quercia et al (2010) and www.google.com

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Source: Quercia et al (2011) and Lazaro et al (2011)

a) b) c)

d) e) f)

g) h)

Precipitated (NaPrecipitated (Na22SiOSiO44)) Pyrogenic (SiClPyrogenic (SiCl44))

Pyrogenic (oil well silica fume)Pyrogenic (oil well silica fume)

Precipitated (NaPrecipitated (Na22SiOSiO44))

Pyrogenic (silica fume slurry)Pyrogenic (silica fume slurry) Pyrogenic (SiClPyrogenic (SiCl44))

Pyrogenic (SiClPyrogenic (SiCl44)) Precipitated (Mg,FePrecipitated (Mg,Fe22SiOSiO44))

Comparison of different silicas

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Nano-silica in concreteSmall particles of

amorphous silica

Pozzolanic

more CSH

Nucleating agent

(accelerating effect)

Consume Ca(OH)2

(anti Ca+2 leaching)

Smaller CSH

gel structure

Improve final

strength

Enhance use

of other filler

Fill in voids

(nano filler)

Improve ITZDenser

packing

Less

porosity

Less free water

(Anti bleeding)

Improved

durability

Improve

toughness

Source: Quercia et al (2010)

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Examples of nano-silica use

Self-compacting concrete case (SCC)

3.8% bwoc of nano-silicaAll properties were improved compared with the reference.



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80 Jaars

Self-compacting concrete case


Source: CUR (2009)



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Self-compacting concrete case



3% NaCl

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Eco-concrete case

The use of nano-silica allows incorporating more recycled aggregates and

alternative fillers such as fly and sludge ashes.

RA 25% lost in

compressive strength.

3.0% of nS increased

compressive strength. Source: Hosseini et al (2010).


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Coating case

The concentrated dispersion of nano-sized silica offer extensive chemical

reaction-sites that penetrate deeply and start reacting forming calcium silica

hydrate (CSH), which strengthens the concrete matrix and increases stain

and waterproofing.Source: Nanoset™ densifier broshure (2010), www.google.com


Other applications and markets

1.89

0.81

2.7 MMt (2014)

Worldwide

Precipitated

Others:

Fumed silica

Silica Gel

Silica sol

Precipitated silica application

Filler in rubber (tires) and plastics

Coating, paints, inks, catalysis support

Abrasives (tooth pastes)

Flowing agent (foods)

6.3%/year

Reference prices

Micro-silica for Concrete:

250 - 500€ per ton

Special silica:

300 - 3000€ per tonSource: (http://www.reportlinker.com/p0204909/World-Specialty-Silicas-Market.html)

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Practical application method and model to used new nS in mortars and concrete mixes.

How?

•Cement replacement with nS (CO2 footprint ↓)

•Add nS � M.P. ↑ (eco-concretes).

•nS+ mix design tool �UHPC (use less materials).

Approach


Thank you for your attention!

Questions?

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Contact details

Eindhoven University of Technology

Department of The Build Environment

P.O. Box 513

5600 MB Eindhoven

The Netherlands

Telephone: +31 (0) 40 247 23 23

Telefax: +31 (0) 40 243 86 95

www.m2i.nl

George Quercia BianchiPhD Researcher

E-mail: [email protected]


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Nanosilica in construction materials - KIVI in construction materials ... Cement Fly ash Powders Natural sand Coarse ... Pyrogenic (silica fume slurry) Pyrogenic