Civil Engineering Reference
In-Depth Information
4.4.2 Hardened Concrete Properties
Etxeberria et al. (
2010
) observed contrasting compressive strength behaviour,
when concrete mixes were prepared by replacing 0, 25, 50 and 100 % by volume
of natural coarse aggregates by BFS aggregates at low and high w/c ratios. At high
w/c, the compressive strength for concrete with BFS aggregates used to replace 25
and 100 % by volume of coarse aggregates was lower than that of the conventional
concrete. But the compressive strength of concrete with BFS aggregates used to
replace 50 % by volume of coarse aggregates was higher than that of the con-
ventional concrete. On the other hand, at low w/c, the compressive strength of
concrete with BFS aggregates was higher than that of the conventional concrete
and strength increased with the content of slag aggregates in concrete. In both
cases, the w/c value of conventional concrete was lower than those of the BFS-
aggregates concrete mixes.
Demirboga and Gul (
2006
) found higher compressive strength for HSC with
BFS as coarse aggregates than for conventional concrete for various w/c values.
However, the difference in strength between BFS-aggregates concrete and con-
ventional concrete decreased as the w/c value increased (Fig.
4.22
). Haque et al.
(
1995
) reported that compressive strength of concrete with BFS aggregates could
be as high as 107 MPa. Yüksel and Bilir (
2007
) observed similar compressive
strength for concrete pavement blocks where 60-80 % by volume of fine aggre-
gates were replaced by equal-size BFS aggregates and for a conventional pave-
ment block. Yüksel et al. (
2011
) observed a decreasing trend of compressive
strength with increasing substitution level of fine NA by BFS aggregates.
Collins and Sanjayan (
1999
) found higher 1-day compressive strength for AAS
concrete with BFS as coarse aggregate than for coarse basalt aggregates (NA)
AAS concrete when both were cured by immersion. However, the compressive
strength of NA AAS at the later stages of immersion curing and sealed curing at all
Fig. 4.22 Compressive
strength of concrete with
natural and BFS coarse
aggregates (Demirboga and
Gul
2006
)
