Civil Engineering Reference
In-Depth Information
Fig. 5.34
Effect of FA on the FS performance of concrete with fine RCA (Ahmed
2011
)
Fig. 5.35 Variation of the
FS of conventional concrete
and RCAC with and without
FA, prepared at w/c of 0.55
and 0.45 (James et al.
2011
)
Gupta et al. (
2011
) observed a reduction of about 6 % in 28-day FS in com-
parison to a 21.5 % reduction in the corresponding CS, due to the replacement of
100 % coarse NA by RCA. On the other hand, the FS of RCAC with FA as a 10 %
replacement of OPC was around 3 % higher than that of conventional concrete and
similar to that of conventional concrete with 10 % FA. The FS of RCAC with
20 % FA, however, was about 20 % lower than that of conventional concrete with
OPC only. Rao and Khan (
2009
) observed reductions of about 4 % in FS due to the
replacement of 50 % (by mass) of coarse NA by coarse RCA. However, the
incorporation of 0.01-0.03 % glass fibre improved the FS of the resulting RCAC.
Tam et al. (
2007
) observed advantages of the use of a two-stage mixing
approach instead of the normal mixing approach to increase several mechanical
