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Geopolymer Concrete for Green Construction Materials(Without
Cement)
Engr.Arivusudar Nagarajan Engr.Arivusudar Nagarajan Special concrete products Special concrete products
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What’s wrong with cement concrete?
• Many concrete structures deteriorate after 20 years.
• Cement production releases high amounts of CO2 to the atmosphere(1tonne of cement production releases 1tonne of CO2) thus contributing to 7% of world CO2 emissions.
• Cement is one of the most energy intensive material.
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How to reduce the use of cement
• Partially replace the use of cement in concrete.example: high volume fly ash concrete
• Develop alternate materials.example:Geopolymer concrete
Geopolymer Concrete• Hardened cementitious paste made from
flyash and alkaline solution.• Combines waste products into useful
product.• Setting mechanism depends on
polymerization.• Curing temp is between 60-90 degree
celcious.
CONSTITUENTS OF GEOPOLYMER CONCRETE
• Source materials : alumina-silicate
Alkaline liquids combination of sodium hydroxide
(NaOH) or potassium hydroxide (KOH) and sodium silicate or potassium silicate.
Preparation of geopolymer concrete
GeopolymerisationStorag
e
Aggregate
Fly ashAlkaline activatorNaOH + Na Silicate
MANUFACTURE OF GEOPOLYMER CONCRETE
The aggregates are prepared in saturated-surface-dry (SSD) condition, and are kept in plastic buckets with lid
Dry Materials of Geopolymer Concrete
The fly ash and the aggregates are first mixed together dry in 80-litre capacity pan mixer
. Pan Mixer Used in the Manufacture of Geopolymer Concrete
The liquid component of the mixture is then added to the dry materials and the mixing continued
usually for another four minutes
Addition of Liquid Component
The fresh concrete could be handled up to 120 minutes without any sign of setting and without any degradation in
the compressive strength
Fresh Geopolymer Concrete Ready for Placing
The workability of the fresh concrete was measured by means of the conventional slump test
Slump Measurement of Fresh Geopolymer Concrete
Boundary between Geopolymer binder , aggregate and reinforcement
ADVANTAGES
Cutting the world’s carbon.The price of fly ash is low. Better compressive strength.Fire proof.Low permeability.Eco-friendly.Excellent properties within both acid and salt
environments.
• Different source materials• Properties of soluble silicate• Contaminants• Industry regulations• New material
Research Context and Prior Work• During the year 2014-15, the per capita electricity generation in India was 1,010
kWh with total electricity consumption (utilities and non utilities) of 938.823 billion or 746 kWh per capita electricity consumption.
• The utilization of fly ash has increased from 6.64 million ton in 1996-97 to a level of 102.54 million-ton in 2014-15.
• Cement Production (179.9 mn tonnes – 2011) , CO2 emissions 167.Mt • Cement production contributes 7% of human CO2 emissions• Cement production - energy intensive process (heat raw materials to 2550 F)
Re-Arranging the Equation
Power Generation Refinery/Chemical industryCement Production
Re-Arranging the Equation
+
Conclusion The reduced CO2 emissions of Geopolymer cements make
them a good alternative to Ordinary Portland Cement.
Produces a substance that is comparable to or better than traditional cements with respect to most properties.
Geopolymer concrete has excellent properties within both acid and salt environments
Low-calcium fly ash-based geopolymer concrete has excellent compressive strength and is suitable for Structural applications.
Thank You [email protected]
