HowNano Technology can change theConcrete World
Outline1. Introduction -> Approach towards Green Building2. What is Nano Technology3. What is Concrete?3.1. Environmental concerns4. Nano Technology in Concrete4.1. Al2O3 Nanoparticles in concrete4.2. Zro2 Nanoparticles in concrete4.3. Tio2 Nanoparticles in concrete4.4. Fe2o3 Nanoparticles in concrete5. Conclusion6. Bibliography
Green Building• The advent of the Nano era in building could not have come at a better time, as the building industry moves aggressively toward sustainability.• Worldwide, buildings consume between 30 and 40 per cent of the world’s electricity.• Green building is a catch-all phrase encompassing efforts to reduce waste, toxicity, and energy and resource consumption in buildings.
Environmental impact of buildingsBuildings figure prominently in world energyconsumption, carbon emissions, and waste.(Source: Levin, “Systematic Evaluation and Assessment ofBuilding Environmental Performance (SEABEP),” Buildings andEnvironment, Paris, June 9-12, 1997)
What is Nano Technology?• Nanotechnology, the understanding and control of matter at dimensions of roughly one to one hundred billionths of a meter, is bringing dramatic changes to the materials and processes of science and industry worldwide.• Nanoparticles have unique mechanical, electrical, optical and reactive properties distinct from larger particles.
What is Concrete ?• Concrete is a composite construction material made primarily with aggregate, cement, and water• Concrete is the world’s most widely used manufactured material• About one ton of concrete is produced each year for every human being in the world (some 6 billion tons per year.)
Environmental Concerns• Energy consumption, carbon emissions and waste are all major environmental concerns connected with concrete production and use• Portland cement, that holds aggregate, water and lime together to make concrete, accounts for about 12 percent of its volume, but 92 percent of its energy demand.• For every ton of cement produced, 1.3 tons of C02 is released into the atmosphere• Worldwide, cement production generates over 1.6 billion tons of carbon, more than 8 percent of total carbon emissions• Concrete accounts for more than two-thirds of construction and demolition waste with only 5 percent currently recycled
Nano Technology in ConcreteNanotechnology is leading to new• Cements,• Concretes,• Admixtures (concrete performance-enhancing additives,)• Low energy cements,• Nano composites, and• Improved particle packing• The addition of nanoparticles, for example, can improve concrete’s durability through physical and chemical interactions such as pore filling
Al2O3 nanoparticles in Concrete• Portland cement was partially replaced by Al2O3 nanoparticles with the average particle size of 15nm with different amount and the specimens were cured in water and saturated limewater for specific ages• Utilizing up to 2.0 wt.% Al2O3 nanoparticles could produce concrete with improved strength and water permeability when the specimens cured in saturated limewater while this content is 1.0 wt.% for the specimens cured in tap water• The high action of fine nanoparticles substantially increases the quantity of C–S–H gel.
SEM micrograph of Al2O3 nanoparticles The properties of Nano- Al2O3Diameter (nm) Surface volume ratio (m2/g) Density (g/cm3) Purity (%) 15 3 155 12 <0.12 > 99.9
Compressive strength of nano-Al2O3 particle blended concrete specimens
SEM micrograph of cement paste without Al2O3 nanoparticles
SEM micrograph of cement paste with Al2O3 nanoparticles cured in water.
Split tensile strength of nano-Al2O3 particle blended concrete specimens
Flexural strength of nano-Al2O3 particle blended concrete specimens
ZrO2 nanoparticles in Concrete Split Tensile strength (MPa) Sample Nano ZrO2 7 days 28 days 90 days Designation particle (%)) C0 (control) 0 1.5 1.8 2.3 N1 0.5 2.5 2.9 3.4 N2 1.0 3.0 3.3 3.6 N3 1.5 2.9 3.0 3.2 N4 2.0 2.0 2.1 2.4 Water to binder [cement + nano-ZrO2] ratio of 0.40
Flexural strength of nano-ZrO2 particle blended cement mortars Flexural strength (MPa) Sample Nano ZrO2 7 days 28 days 90 days Designation particle (%)) C0 (control) 0 4.2 4.4 4.7 N1 0.5 5.0 5.3 5.5 N2 1.0 5.5 5.8 6.2 N3 1.5 5.2 5.6 5.9 N4 2.0 4.8 5.0 5.2 Water to binder [cement + nano-ZrO2] ratio of 0.40
TiO2 nanoparticles in Concrete Split Tensile strength (MPa) Sample Nano TiO2 7 days 28 days 90 days Designation particle (%)) C0 (control) 0 1.5 1.8 2.3 N1 0.5 2.3 2.6 2.9 N2 1.0 2.8 3.0 3.3 N3 1.5 2.6 2.7 3.0 N4 2.0 1.9 1.9 2.4 Water to binder [cement + nano-TiO2] ratio of 0.40
Flexural strength of nano-TiO2 particle blended cement mortars Flexural strength (MPa) Sample Nano TiO2 7 days 28 days 90 days Designation particle (%)) C0 (control) 0 4.2 4.4 4.7 N1 0.5 4.9 5.1 5.6 N2 1.0 5.6 5.5 6.1 N3 1.5 5.1 5.4 5.7 N4 2.0 4.5 5.1 5.0 Water to binder [cement + nano-TiO2] ratio of 0.40
Fe2O3 nanoparticles in Concrete Flexural strength (MPa) Sample Nano Fe2O3 7 days 28 days 90 days Designation particle (%)) C0 (control) 0 27.3 36.8 42.3 N1 0.5 30.1 41.0 44.5 N2 1.0 31.2 42.5 46.1 N3 1.5 31.0 41.9 45.2 N4 2.0 28.1 38.9 43.8 Water to binder [cement + nano-Fe2O3] ratio of 0.40
Nano technology and Self healing concrete• When self-healing concrete cracks, embedded microcapsules rupture and release a healing agent into the damaged region through capillary action• They could increase the life of structural components by as much as two or three times
The results show that the specimens containing Al2O3nanoparticles; nano-ZrO2; nano-Tio2; nano-Fe2O3 havesignificantly higher strength with comparison to that ofspecimens without Nano particles at every age of curingBy these results we can expect a new generation ofconstruction and a step closer to Sustainable development