Civil Engineering Reference
In-Depth Information
Fig. 6.1 Ratio between the
28- and 90-day compressive
strengths of concrete versus
the ratio between the
densities (top), the water
absorptions (centre) of the
mixture of aggregates and the
7-day compressive strengths
of concrete (bottom)
1.05
y = -1.7693x + 1
R
2
= 0.837
0.95
0.85
0.75
Kou et al
Leite
Soberón
Carrijo
0.65
0.55
0
0.05
0.1
0.15
0.2
0.25
1-D
RAC
/D
RC
1.05
y = -0.0308x + 1
R
2
= 0.625
0.95
0.85
0.75
Leite
Soberón
Carrijo
0.65
0.55
0
2
4
6
8
10
12
wa
RAC
/wa
RC
-1
1.05
y = -1.2045x + 1
R
2
= 0.6664
0.95
0.85
0.75
Kou et al
Leite
Soberón
0.65
0.55
-0.1
0
0.1
0.2
0.3
1-f
c7RAC
/f
c7RC
6.3.4.2 Modulus of Elasticity
Modulus of elasticity results were obtained from the campaigns of Carrijo (
2005
),
Leite (
2001
), Kou et al. (
2004
) and Gomez-Soberón (
2002
). In every case, the
modulus of elasticity decreases when the NA/RA replacement ratio increases. This
behaviour is mostly attributed to the lower stiffness of RA compared with NA. The
higher porosity of RA is responsible for the higher deformation of these aggregates
when compared with NA, and this effect is also reflected in concrete with RA
when compared to conventional concrete.
