Fly Ash in East Tennessee

1. Fly Ash in East Tennessee Joe Sponcia Southeastern Fly Ash Co.

3. Chemical Interaction of Fly Ash with Concrete-Making Materials When Portland cement hydrates, calcium hydroxide is formed. Approximately 20% of the weight of Portland cement is converted to calcium hydroxide Does not strengthen concrete. Calcium hydroxide is soluble in water and may be removed by leaching action. When fly ash is employed, hydrated lime combines with fly ash to form a stable cementitious compound. Helps strengthen concrete.

4. Typical Chemistry Portland Cement Fly Ash 21.95% Silica 52.8% 5.1% Alumina 22.3% 63.8% Lime trace 2.4% Iron 9.2% 2.4% Sulphur 0.7% 2.7% Magnesia 0.2% 0.5% Alkalines 0.5% 1.2 LOI 3.7 3.15 Specific Gravity 2.30

5. Mechanical Interaction of Fly Ash with Concrete-Making Materials Fly Ash particles act as �ball bearings.� Fine aggregate gradation and texture determine the amount of water reduction. Fly Ash can give 1-3 gallon water reduction per cubic yard.

6. Typical Concrete Mix Designs 3000 PSI w/ Fly Ash Cement 350 (lbs.) Fly Ash 150 Coarse Agg. 1750 Fine Agg. 1370 Water 32 gallons Air 5% 3000 PSI w/o Fly Ash Cement 440 (lbs.) Coarse Agg. 1750 Fine Agg. 1460 Water 32 gallons Air 5%

7. Typical Concrete Mix Designs 4000 PSI w/ Fly Ash Cement 420 (lbs.) Fly Ash 150 Coarse Agg. 1750 Fine Agg. 1320 Water 32 gallons Air 5% 4000 PSI w/o Fly Ash Cement 540(lbs.) Coarse Agg. 1750 Fine Agg. 1390 Water 32 gallons Air 5%

8. Technical Advantages of Fly Ash in Plastic Ready Mixed Concrete Reduced Water Requirement Increases Workability Reduces Bleeding Reduces Segregation Reduces Heat of Hydration

9. Technical Advantages of Fly Ash in Hardened Ready Mixed Concrete Reduces Drying Shrinkage Improves Water Tightness in Concrete Reduces Alkali-Silica Reactivity in Concrete Improves Resistance of Sulfate and Acid Attack Long Term Strength Gain