3. INTRODUCTION
1) Geo polymer concrete is nothing but a
replacement of cement concrete.
2) Cement is not used as binding materials.
3)Fly ash and alkali solution is used as binder.
4)It gives early strength
5)High compressive strength
6)Reduces co2 emission
4. What is 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.
5. 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
6. What is 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.
7. Materials required
Source materials :
alumina-silicate
Alkaline liquids :
combination of sodium hydroxide
(NaOH) or potassium hydroxide
(KOH) and sodium silicate or
potassium silicate.
8. Preparation of geopolymer concrete
Geopolymerisation
Storage
Aggregate
Fly ash
Alkaline activator
NaOH + Na Silicate
9. 2.Geopolymer Concrete :Process
• Alkaline solutions induce the Si and Al atoms in
the source materials ,example fly ash , to
dissolve.
• Gel formation is assisted by applying heat.
• Gel binds the aggregates ,and the unreacted
source material to form the Geopolymer
concrete.
12. The aggregates are prepared in saturated-surface-dry
(SSD) condition, and are kept in plastic buckets with
lid
13. The fly ash and the aggregates are first mixed together
dry in 80-litre capacity pan mixer
14. The liquid component of the mixture is then added to the
dry materials and the mixing continued usually for
another four minutes
15.
16. Fresh Geopolymer Concrete Ready for Placing
The fresh concrete could be handled up to 120 minutes
without any sign of setting and without any degradation
in the compressive strength
17. 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.
ADVANTAGES
18. 4.Applications of GPC
• Pre-cast concrete products like railway sleepers,electric power poles
etc.
• Marine structures
• Waste containments etc..
19. • High cost of alkaline solution
• Practically steam curing is difficult
• Bringing of source material to location
• Industry regulations
• New material
20. 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.
Geo polymer 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.
