Benefits - Strength
BASF's MetaMax® can create concrete compressive strengths as high as 18,000 psi (124 MPa). Even when such ultra-high strength is not required, MetaMax is a cost effective way to boost concrete strength for more typical structural requirements. The additional capacity provided by metakaolin can be used to create longer spans, stronger structures and smaller cross sections for more efficient concrete construction.
Two significant mechanisms are responsible for the structural benefits of MetaMax:
- MetaMax is a highly reactive pozzolan: It aggressively converts the lime produced as a byproduct of cement hydration into additional calcium silicate hydrate (CSH) - the interlocking crystals that bind together to give concrete its strength.
- MetaMax particles act as micro-filler: While concrete may seem like a solid material, it contains numerous microscopic pores and voids formed by excess water in a concrete mixture. The tiny particles of MetaMax extend the cement paste so it fills these gaps and makes more contact with the aggregates in concrete.
Moreover, MetaMax high reactivity metakaolin improves both the early and ultimate strength of concrete. Benefits of higher early strength include:
- Earlier removal of concrete from forms or molds for faster construction cycles.
- Reduced need for shoring and earlier loading of structure.
- Financial savings associated with reduced construction time.
The graph compares typical high strength concrete mixtures made with high reactivity metakaolin and silica fume; HRM meets or exceeds the performance of silica fume at all stages of strength development and attains compressive strengths in excess of 10,000 psi (72 MPa).
