Skip to main content Accessibility help
×
Home

Microstructural Gradients in Cement Paste Around Aggregate Particles

  • Karen L. Scrivener (a1) and Ellis M. Gartner (a2)

Abstract

The effectiveness of condensed silica fume as a strength enhancing additive in concrete has been attributed to its ability to modify the interfacial zone between paste and aggregate. This paper describes a microstructural investigation of this interface using backscattered electron (bse) imaging combined with quantitative image analysis.

Composite specimens were made in which a single piece of aggregate was embedded in cement paste. Granite, dolomite and garnet aggregates were used. After curing, the specimens were sectioned perpendicular to the surface of the aggregate particles and polished. The variation in porosity, amount of anhydrous material and calcium hydroxide (CH), with distance from the aggregate surface was measured. It was found that the porosity increases in the paste close to the interface, while the content of anhydrous grains decreases. No significant increase in CH content was found near the interface.

The results confirm the applicability of the bse - image analysis technique, but indicate that the interfaces in specimens prepared in this manner may not be representative of aggregate paste interfaces in concrete.

Copyright

References

Hide All
1. Bentur, A., A. Goldman & M.D. Cohen, this proceedings
2. Barnes, B.D., Diamond, S. & Dolch, W.L., J.Am.Ceram.Soc., 62, 2124, (1978).
3. Scrivener, K.L. & Pratt, P.L., Proc. 6th Int. Conf. on-Cement Microscopy, Alberquerque, New Mexico 1984 pp145155.
4. Scrivener, K.L., PhD Thesis, University of London, 1984
5. Scrivener, K.L., in Research on the Manufacture and Use of Cements, ed Frohnsdorff, G. (Engineering Foundation, 1985) pp117119.
6. Scrivener, K.L. & Pratt, P.L., Proc 8th Int Cong. Chem. Cement, Rio de Janerio, 1986, Vol III, pp466471.
7. Farran, J., Revue des materiaux de construction, n° 490–491–492, 1956
8. Grandet, J. & Ollivier, J.P., Proc 7th Int. Cong. Chem. Cement, Paris 1980, Vol III, ppVII85-89.
9. Grandet, J. & Ollivier, J.P., Proc 7th Int. Cong. Chem. Cement, Paris 1980, Vol III, ppVII63-68.
10. Monteiro, P.J.M. and Mehta, P.K., Cem. & Conc. Res. 15, 378–80, (1985).
11. Monteiro, P.J.M., Maso, J.C. and Ollivier, J.P., Cem. & Conc. Res. 15, 953958, (1985).
12. Scrivener, K.L. & Bentur, A., to be published
13. Goult, D. & Pratt, P.L., private communication
14. Hadley, D.H., PhD thesis, Purdue University, USA, 1972.
15. Rosenberg, A.M. and Gaidis, J.M., presented at the 2nd. International Conference on The Use of Fly Ash, Silica Fume, Slag and Natural Pozzolans in Concrete, Madrid, Spain, April 1986.

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed