Nanotechnology of Concrete · 2018. 3. 26. · Other Concrete Nanoparticles Nano-calcium carbonate (Nano-CaCO3) Nano-clays Electric arc furnace dust (Nano-ZnFe2O4) Nanoalumina (Nano
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Nanotechnology of Concrete
Virginia Concrete Conference
March 2-3, 2017
Jeremy Betts
1
Nanotechnology
World of the extremely small
How Small?
3
Sobolev
2016
CSH Nano Structure
4
Nano Characterization (tests)
Nano indentation
Nano Scratch
Ultrasonic Atomic Force Microscopy
X-ray diffraction (XRD)
5
Nano Indentation
6
Nano scratch
7
Ultrasonic Atomic Force Microscopy
8
XRD
9
Making Nano Materials
10
Making Nano Materials
Top Down Bottom Up
11
Nano assembly
Biomemetics
12
Advanced Fibers
13
Superhydrophobic Concrete
14
Superhydrophobic Concrete
15
Superhydrophobic Concrete
16
Self Monitoring Concrete (piezoresistive property)
17
Current Application of Nanoparticles
18
Nano-silica (nano-SiO2)
Properties
Accelerates hydration reactions
and dissolution of C3S
Accelerates pozzolanic effect of fly ash
Denser packing of hydration
products
Increases viscosity (thicker)
Reduced bleed water
Longer mixing required
19
Nano-silica (nano-SiO2)
Properties
Decreases porosity
Improved compressive strengths
Improved Flexural Strengths
Increased abrasion resistance
ASR mitigation
Pozzolanic effect higher than that
of silica fume
20
Nano-silica (nano-SiO2)
Where has it been used?
RMG (Rock matching Grout)
SCC
Cementitious pavement coating
Viscosity Modifier
Accelerator
21
Nano-titanium dioxide (Nano-TiO2)
22
Nano-titanium dioxide (Nano-TiO2)
Photocatalysis
Pollutants (and stains) are
destroyed through molecular
adsorption and oxidative reaction
processes
Ultimate products : CO2, H2O,
NO3-, SO42-, O2, Cl-, ...
Catalyst remains indefinitely
23
Nano-titanium dioxide (Nano-TiO2)
Properties
Does not noticeably alter fresh
concrete properties (basic)
De- polluting
Self Cleaning
24
Nano-titanium dioxide (Nano-TiO2)
Where has it been used?
All Types of Concrete
Stucco
Cementitious coatings
Monuments
Buildings
Roadways
25
Carbon Nanotubes/Nanofibers
26
Carbon Nanotubes/Nanofibers
Nanotubes (CNT)
27
Nano Fibers (CNF)
Carbon Nanotubes/Nanofibers
Properties
Compressive and flexural strength
enhancement
Chemical resistance
Electromagnetic shielding
Self sensing capabilities
Abrasion resistance
Shrinkage reduction
Decreased permeability
Increases Viscosity
Dispersion agent recommended
28
Carbon Nanotubes
Where has it been used?
Several concrete mix types
Bulidings
Road repair (approved by GDOT)
Further research needed
29
Other Concrete Nanoparticles
Nano-calcium carbonate (Nano-
CaCO3)
Nano-clays
Electric arc furnace dust (Nano-
ZnFe2O4)
Nanoalumina (Nano Al2O3)
Nanoiron (Nano Fe2O3)
30
Nano-composites
New generation chemical
admixtures
– PCP (polycarboxylate-based polymers )
– Controlled release
technology
31
Environmental Effects and Safety of Nanomaterials
Used in Concrete
Safety Precautions
– Respiration
– Ingestion
Environmental Precautions
– Agglomeration
32
Upcoming ACI Publication
33
Questions?
34
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