The behavior of Self-Compacting Concrete (SCC) is very sensitive to the use of by-products
in replacement of conventional cement or finer aggregate fractions. The high proportions
of these raw materials in SCC can in great part explain this performance. 18 SCC mixes of
slump-flow class SF3 were prepared for a thorough evaluation of different sustainable
materials and for the prediction of their effects as binder or fine/powder aggregate on the
mechanical properties of SCC. The mixes incorporated 100% coarse Recycled Concrete
Aggregate (RCA); different amounts (0%, 50% or 100%) of fine RCA; CEM I ordinary Portland
cement and CEM III/A (with 45% ground granulated blast furnace slag); and more sustainable powders compared to conventional limestone filler <0.063 mm (such as limestone
powder 0/0.5 mm and RCA powder 0/0.5 mm). Flowability, hardened density, strength
under compression, tensile and bending stresses and modulus of elasticity were all studied. The addition of 50% fine RCA yielded an SCC of adequate strength, stiffness and
flowability. SCC manufactured with limestone powder 0/0.5 mm showed the best overall
performance, while SCC behavior was improved when adding CEM III/A by adjusting the
mix composition. The experimental results of all the mechanical properties were
compared with the values predicted by the compressive-strength-based formulas from the
European and USA standards. Overall, the values resulting from those expressions overestimated all the mechanical properties. Therefore, since all these properties followed
the same simple-regression trend, a statistical analysis was performed to develop a global
model capable of accurately predicting them all.
