High-temperature performance of mortars and concretes based on alkali-activated slag/metakaolin blends


  • S. A. Bernal Universidad del Valle - University of Melbourne
  • R. Mejía de Gutiérrez Universidad del Valle
  • F. Ruiz Universidad del Valle
  • H. Quiñones Universidad del Valle
  • J. L. Provis University of Melbourne




alkali-activated binders, high temperatures, granulated blast-furnace slag, metakaolin, mechanical properties


This paper assesses the performance of mortars and concretes based on alkali activated granulated blastfurnace slag (GBFS)/metakaolin (MK) blends when exposed to high temperatures. High stability of mortars with contents of MK up to 60 wt.% when exposed to 600 °C is identified, with residual strengths of 20 MPa following exposure to this temperature. On the other hand, exposure to higher temperatures leads to cracking of the concretes, as a consequence of the high shrinkage of the binder matrix and the restraining effects of the aggregate, especially in those specimens with binders containing high MK content. A significant difference is identified between the water absorption properties of mortars and concretes, and this is able to be correlated with divergences in their performance after exposure to high temperatures. This indicates that the performance at high temperatures of alkali-activated mortars is not completely transferable to concrete, because the systems differ in permeability. The differences in the thermal expansion coefficients between the binder matrix and the coarse aggregates contribute to the macrocracking of the material, and the consequent reduction of mechanical properties.


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How to Cite

Bernal, S. A., Mejía de Gutiérrez, R., Ruiz, F., Quiñones, H., & Provis, J. L. (2012). High-temperature performance of mortars and concretes based on alkali-activated slag/metakaolin blends. Materiales De Construcción, 62(308), 471–488. https://doi.org/10.3989/mc.2012.01712



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