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Aluminum Sulfate Hydration Retarders for High-Calcium Fly Ash Used in Highway Construction

Published online by Cambridge University Press:  25 February 2011

M. Tohidian  and
Joakim G. Laguros
M. Tohidian
Affiliation:
Standard Testing and Engineering, Oklahoma City, Oklahoma
Joakim G. Laguros
Affiliation:
School of Civil Engineering and Environmental Science, The University of Oklahoma, Norman Oklahoma 73019, USA
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Abstract

The rapid hydration and setting associated with the use of high-calcium fly ash as an additive in soil and aggregate base stabilization in highway construction imposes certain limitations in regards to operational time and volume of work executed. Aluminum sulfate and its ammonium salt were evaluated as hydration reaction retarders. Mixtures of Ottawa sand and Class C high lime fly ash in a 1:1 weight ratio were used for the evaluations. These additives minimized the adverse effects of delayed compaction by recovering some of the compressive strength lost to the rapid hydration, although in all cases the density of the mixes decreased. The recovery of strength was related to the heat of hydration, wherein the peak temperature was reduced from 90°F to the range of 86–78°F at 2 hours; further temperature decreases were observed as reaction time increased. The availability of the sulfate ions, as manifested by the presence of ettringite, helps the hydration process continue, minimizes the adverse effects of delayed compaction and assists positively in the reduction of the void area of mixes and in stratlingite formation, which contributes to a strong crystalline framework.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 86: Symposium N – Fly Ash and Coal Conversion By-Products III , 1986 , 171
Copyright
Copyright © Materials Research Society 1987

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References

REFERENCES

1. Laguros, J.G. and Keshawarz, M.S., in Fly Ash and Coal Conversion By-Products: Characterization, Utilization and Disposal II, edited by McCarthy, G.J., Glasser, F.P. and Roy, D.M., Mat. Res. Soc. Symp. Proc. Vol.65 (Materials Research Society, Pittsburgh, 1986) pp. 37–46.Google Scholar
2. Arman, A., and Dantin, T.J., The Effect of Admixtures on Layered Systems Constructed with Soil-Cement, Eng. Res. Bull. No. 86, (Louisiana State University Division of Engineering Research, Baton Rouge 1965).Google Scholar
3. Laguros, J.G., A Study of Aggregate-Fly Ash Mixes (Department of Civil Engineering, University of Oklahoma, Norman, 1981) 20 pp.Google Scholar
4. Thornton, S.I. and Parker, D.C., Construction Procedures Using Self-Hardening Fly Ash, FHWA-AR-80, September 1980.Google Scholar
5. Thornton, S.I. and Parker, D.G., Fly Ash as Fill and Base Material in Arkansas Highways. Highway Research Project 43, October 1975.Google Scholar
6. Laguros, J.G., and Davidson, D.T., Highway Research Board Record 36, 1963.Google Scholar
7. Lea, F.M., The Chemistry of Cement and Concrete, Third Edition, (Chemical Publishing Company, Inc., London, 1970).Google Scholar
8. Lorprayoon, V. and Roosington, D.R., Cem. Concr. Res. 11, 267–277 (1981)Google Scholar
9. Watanbl, Y., Suzuki, S. and Nishi, S., Journal of Research, Onado Cement Company, Volume 1, 1969, p. 184–196.Google Scholar
10. Young, J.F., Transportation Research Record 564, 1–10 (1976).Google Scholar
11. Minnick, J.L., in Proceedings Fly Ash Utilization Symposium, Bureau of Mine Information Circular No. 8488, (U.S. Department of Interior, Washington, DC, 1970).Google Scholar
12. McClune, W.F., Editor-in-Chief, Powder Diffraction File (JCPDS-International Centre For Diffraction Data, Swarthmore, PA).Google Scholar