Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-29T07:27:38.253Z Has data issue: false hasContentIssue false

Pore Structure Development in Portland/Fly Ash Blends

Published online by Cambridge University Press:  25 February 2011

David J. Cook
Affiliation:
National Building Technology Center, Chatswood, NSW 2067, Australia.
Huu T. Cao
Affiliation:
National Building Technology Center, Chatswood, NSW 2067, Australia.
Everett P. Coan
Affiliation:
University of New South Wales, Kensington, NSW 2033, Australia.
Get access

Abstract

Pore structure development in portland/fly ash blends was investigated using mercury porosimetry and methanol exchange techniques. The progress of hydration was monitored using compressive strength tests. The specimens were made using four water-cement ratios and were hydrated over a one-year period in lime-saturated water. Mercury porosimetry results indicated that the blended cement pastes generally had higher total porosity than plain cement pastes. The major contribution to this increase in porosity was in the form of smaller pore sizes. With reactive fly ash at 20% replacement, the pore structure of mature paste consists mainly of pores nominally smaller than 0.05 μm in diameter. Diffusion parameters obtained from the methanol exchange results were found to be inversely related to the volume of large pores (nominally <0.05 μm) and also to the volume of small pores (nominally <0.05 μm). The effects of the physical and chemical properties of cements and fly ashes on pore structure development are discussed.

Type
Research Article
Copyright
Copyright © Materials Research Society 1987

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Mehta, P.K., in Performance of Concrete in Marine Environment, edited by Malhotra, V.M. (ACI SP 65, Detroit 1980) pp. 120.Google Scholar
2. Feldman, R.F., in Proc. 1st Int. Conf. on the Use of Fly Ash, Silica Fume and Other Mineral By-Products in Concrete, Montebello, 1983 (ACI SP 79, 1983) 1, pp. 415434.Google Scholar
3. Hughes, D.C., Mag. Concr. Res. 37, (133) 227233 (1985).Google Scholar
4. Parrott, L.J., Mater. Constr. (Paris).17, (98) 131137 (1984).Google Scholar
5. Mehta, P.K. and Manmohan, D., Proc. Int. Congr. Chem. Cem., 7th, 1980 3, VII 15 (1980).Google Scholar
6. Parrott, L.J., Patel, R.G., Killoh, D.C. and Jennings, H.M., J. Am. Ceram. Soc. 67(4), 233237 (1984).Google Scholar
7. Mindess, S. and Young, J.F., Concrete (Prentice-Hall, 1981) p. 99.Google Scholar
8. Halse, Y., Pratt, P.L., Dalziel, J.A. and Gutteridge, W.A., Cem. Concr. Res. 14, 491498 (1984).CrossRefGoogle Scholar
9. Dalziel, J.A., Technical Report 555 (Cement and Concrete Association, Wexham Springs, 1983).Google Scholar
10. Patel, R.G., Parott, L.J., Martin, J.A. and Killoh, D.C., Cem. Concr. Res. 15, 343356 (1985).Google Scholar
11. Parrott, L.J., Cem. Concr. Res. 13, 1822 (1983).Google Scholar