As can be seen in Figs. 6a, 7a and 8a and b, the cement paste was
homogenous with both aggregate types. Further, there was no difference
(e.g., densification) in the cement paste at the aggregate
boundary. These observations were also confirmed by the distribution
of elements determined by SEM/EDS (Energy Dispersive X-ray
Spectroscopy); for example, the distribution of Ca demonstrated
that the cement paste was uniformly dispersed in the investigated
zone (Figs. 6b and 7b). The distribution of magnesium (Mg) corresponded
to the dolomite aggregate grain, and that of silicon (Si) to
the fine fraction, which was quartz (Fig. 6c and d, respectively). In
the case of Fig. 7c, the distribution of Fe corresponded to the slag
aggregate, and Ca and Si (Fig. 7b and d, respectively) to the cement
paste and quartz. In both cases (Figs. 6d and 7d), Si was within the
cement paste, but the zones that represented quartz were much
brighter because of the high concentration of Si.