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Design and Preparation of Metakaolin-Based Mineral Admixture and its Effects on the Durability of Concrete

  • Zhonghe Shui
  • Kai YuanEmail author
  • Tao Sun
  • Qiu Li
  • Weineng Zeng
Conference paper
Part of the RILEM Bookseries book series (RILEM, volume 10)

Abstract

Many attempts have been made to find a highly-effective way to improve concrete durability. Metakaolin-based mineral admixtures were designed and produced for this purpose and their effects on concrete durability were investigated in this study. The design principles of the admixture were based on the match of the potential active ingredients, such as active SiO2 and Al2O3, among the major active mineral materials including metakaolin (MK), fly ash (FA) and limestone powder (LSP). The proportions of MK, FA and LSP in the admixtures were determined by triangle phase diagram of CaO-SiO2-Al2O3. Based on the above principle, three MK-based mineral admixtures were designed and applied in the concrete by substituting ordinary Portland cement, namely C1 (5 wt%MK + 2 wt%FA), C2 (7 wt%MK + 2 wt%FA + 2 wt%LSP) and C3 (9 wt%MK + 2 wt%FA + 2 wt%LSP). Finally, the effects of the admixtures on the durability of concrete were studied by a range of analytical techniques. The chloride permeability resistance of concrete was significantly improved with the addition of the admixtures. The chloride diffusion coefficient decreased by over 50 % at 56 days. The admixture significantly reduced the shrinkage strain of concrete, and further decrease occurred with the increase of limestone powder content and metakaolin content in admixtures. Improvement of concrete performance resulted from the increase of amount of hydration products, refinement of pore structure and densification of interfacial transition zone (ITZ) caused by the admixture.

Keywords

Portland Cement Ordinary Portland Cement Coarse Aggregate Hydration Product Mineral Admixture 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Notes

Acknowledgments

This research is financially supported by YangFan Innovative & Entrepreneurial Research Team Project (No. 201312C12).

References

  1. 1.
    Ambroise, J., Murat, M., Pera, J.: Hydration reaction and hardening of calcined clays and related minerals. Cem. Concr. Res. 15, 261–268 (1985)CrossRefGoogle Scholar
  2. 2.
    Ding, J., Li, Z.: Effects of metakaolin and silica fumeon properties of concrete. ACI Mater. J. 99(4), 393–398 (2002)Google Scholar
  3. 3.
    Chindaprasirt, P., Homwuttiwong, S., Sirivivatnanon, V.: Influence of fly ash fineness on strength, drying shrinkage and sulfate resistance of blended cement mortar. Cem. Concr. Res. 34, 1087–1092 (2004)CrossRefGoogle Scholar
  4. 4.
    Khatib, J.M.: Wild S pore size distribution of metakaolin paste. Cem. Concr. Res. 26(10), 1545–1553 (1996)CrossRefGoogle Scholar
  5. 5.
    Paiva, H., Velosa, A., Cachim, P., Ferreira, V.M.: Effect of metakaolin dispersion on the fresh and hardened state properties of concrete. Cem. Concr. Res. 42, 607–612 (2012)CrossRefGoogle Scholar
  6. 6.
    Hewlett, P.C.: Chemistry of Cement and Concrete. Butterworth-Heinemann, Oxford (2001)Google Scholar
  7. 7.
    Rodger, S.A., Groves, G.W.: Electron microscopy study of an ordinary portland cement and ordinary portland cement-pulverized fuel ash blended pastes. J. Am. Ceram. Soc. 72(6), 1037–1039 (1989)CrossRefGoogle Scholar
  8. 8.
    Harrisson, A.M., Winter, N.B., Taylor, H.F.W.: An examination of some pure and composite portland cement pastes using scanning electron microscopy with X-ray analytical capabilities. In: 8th International Congress on the Chemistry of Cement, vol. IV, pp. 170–175. Rio de Janeiro (1986)Google Scholar
  9. 9.
    Richardson, I.G., Groves, G.W.: Microstructure and microanalysis of hardened ordinary cement paste. J. Mater. Sci. 28, 265–277 (1993)CrossRefGoogle Scholar

Copyright information

© RILEM 2015

Authors and Affiliations

  • Zhonghe Shui
    • 1
    • 2
  • Kai Yuan
    • 1
    • 2
    Email author
  • Tao Sun
    • 1
  • Qiu Li
    • 1
  • Weineng Zeng
    • 3
  1. 1.State Key Laboratory of Silicate Materials for ArchitecturesWuhan University of TechnologyWuhanChina
  2. 2.School of Materials Science and TechnologyWuhan University of TechnologyWuhanChina
  3. 3.Maoming Kaolin Science and Technology CompanyMaomingChina

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