Title:
Chemical and Physical Sulfate Attack on Fly Ash Concrete Mixtures
Author(s):
Rajaram Dhole, Michael D. A. Thomas, Kevin J. Folliard, and Thano Drimalas
Publication:
Materials Journal
Volume:
116
Issue:
4
Appears on pages(s):
31-42
Keywords:
fly ash; silica fume; sulfate attack; ultra-fine fly ash (UFFA)
DOI:
10.14359/51716678
Date:
7/1/2019
Abstract:
Fly ash concrete mixtures were tested for the chemical and physical sulfate attack. Concrete mixtures consisting of ratios of fly ashes, Type I cement, silica fume, and ultra-fine fly ash (UFFA) were tested. Four exposure conditions were simulated by subjecting the concrete specimens to: 1) immersion in 5% Na2SO4 solution; 2) wet-dry cycling in 5% Na2SO4 solution at 23°C (73°F, wet) and 38°C (100°F, dry); 3) immersion in saturated CaSO4 solution; and 4) wet-dry cycling in saturated CaSO4 solution at 23°C (73°F, wet) and 38°C (100°F, dry). Control specimens were stored in water at ambient temperature. Performance of the concrete mixtures was studied through visual inspection and by monitoring the changes in mass, length, and dynamic modulus of elasticity over time. It was found that improved sulfate resistance can be provided to the fly ash concrete by controlling water-cement ratio (w/c) and blending with Class F fly ash, UFFA, and silica fume.
Related References:
1. Mangat, P. S., and Khatib, J. M., “Influence of Fly Ash, Silica Fume, and Slag on Sulfate Resistance of Concrete,” ACI Materials Journal, V. 92, No. 5, Sept.-Oct. 1995, pp. 542-552.
2. Thomas, M. D. A.; Shehata, M. H.; Shashiprakash, S. G.; Hopkins, D. S.; and Cail, K., “Use of Ternary Cementitious Systems Containing Silica Fume and Fly Ash in Concrete,” Cement and Concrete Research, V. 29, No. 8, 1999, pp. 1207-1214. doi: 10.1016/S0008-8846(99)00096-4
3. Mehta, P. K., “Sulfate Attack on Concrete: Separating Myths from Reality,” Concrete International, V. 22, No. 8, Aug. 2000, pp. 57-61.
4. Skalny, J.; Marchand, J.; and Odler, I., Sulfate Attack on Concrete, Spon Press, London, UK, 2002, 217 pp.
5. Hime, W. G., and Mather, B., “Sulfate Attack or is It?” Cement and Concrete Research, V. 29, No. 5, 1999, pp. 789-791. doi: 10.1016/S0008-8846(99)00068-X
6. Wee, T. H.; Suryavanshi, A. K.; Wong, S. F.; and Rahman, A. K., “Sulfate Resistance of Concrete Containing Mineral Admixtures,” ACI Materials Journal, V. 97, No. 5, Sept.-Oct. 2000, pp. 536-549.
7. Tikalsky, P. J., and Carrasquillo, R. L., “Influence of Fly Ash on the Sulfate Resistance of Concrete,” ACI Materials Journal, V. 89, No. 1, Jan.-Feb. 1992, pp. 69-75.
8. Mehta, P. K., “Effect of Fly Ash Composition on Sulfate Resistance of Cement,” ACI Journal Proceedings, V. 83, No. 6, Nov.-Dec. 1986, pp. 994-1000.
9. Wedding, P. A., and Dunstan, E. R., “A Possible Method for Identifying Fly Ashes that Will Improve the Sulfate Resistance of Concretes,” Cement, Concrete and Aggregates, V. 2, No. 1, 1980, pp. 20-30. doi: 10.1520/CCA10175J
10. Folliard, K. J., and Sandberg, P., “Mechanisms of Concrete Deterioration by Sodium Sulfate Crystallization,” Third International ACI/CANMET Conference on Concrete Durability, SP-145, American Concrete Institute, Farmington Hills, MI, 1994, pp. 933-946.
11. Hime, W. G.; Martinek, R. A.; Backus, L. A.; and Marusin, S. A., “Salt Hydration Distress,” Concrete International, V. 23, No. 10, Oct. 2001, pp. 43-50.
12. Shashiprakash, S. G., and Thomas, M. D. A., “Sulfate Resistance of Mortars Containing High-Calcium Fly Ashes and Combinations of Highly Reactive Pozzolans and Fly Ash,” Seventh CANMET/ACI International Conference on Fly Ash, Silica Fume, Slag, and Natural Pozzolans in Concrete, SP-199, American Concrete Institute, Farmington Hills, MI, 2001, pp. 221-237.
13. Moon, H.; Lee, S.; and Kim, S., “Sulfate Resistance of Silica Fume blended Mortars exposed to various Sulfate Solutions,” Canadian Journal of Civil Engineering, V. 30, No. 4, 2003, pp. 625-636. doi: 10.1139/l03-024
14. Dhole, R.; Thomas, M. D. A.; Folliard, K. J.; and Drimalas, T., “Sulfate Resistance of Mortar Mixtures of High-Calcium Fly Ashes and Other Pozzolans,” ACI Materials Journal, V. 108, No. 6, Nov.-Dec. 2011, pp. 645-654.
15. Bucea, L.; Sirivivatnanon, V.; and Khatri, R., “Building Materials Deterioration Due to Sulfate Attack,” Internal Technical Report, CMIT, CSIRO, 2005, 38 pp.
16. Stark, D., “Performance of Concrete in Sulfate Environment,” Research and Development Bulletin RD 129, Portland Cement Association, Skokie, IL, 2002.
17. Dhole, R., “Sulfate Resistance of High Calcium Fly Ash Concrete,” PhD thesis, University of New Brunswick, Fredricton, NB, Canada, 2010, 273 pp.