Civil Engineering Reference
In-Depth Information
Table 13.4
Tensile strength (flexural) of concrete with aggregates replaced by
rubber particles (Aiello and Leuzzi, 2010)
Mixture
Tensile strength
Tensile strength
(MPa)
decrease (%)
Reference concrete with rubber waste
3.51
-
replacing coarse aggregates (W/B = 0.52)
25% rubber vol.
2.93
16.6
50% rubber vol.
2.52
28.2
75% rubber vol.
2.52
28.2
Reference concrete with rubber waste
5.34
-
replacing fine aggregates (W/B = 0.60)
15% rubber vol.
5.10
4.49
50% rubber vol.
5.03
5.81
75% rubber vol.
4.95
7.30
damping ratio (self-capacity to decrease the amplitude of free vibrations) for
concrete containing 20% rubber particles. other authors (Zheng et al., 2008a,
2008b) confirmed the high damping potential of rubber waste concrete. They
mentioned that concrete with ground rubber shows a 75.3% increase in the
damping ratio and a 144% for crushed rubber concrete (Fig. 13.6).
Fioriti et al. (2007) found that concrete paving blocks containing 8% of
tyre rubber waste have a resistant impact of almost 300% when compared
to the reference concrete. ling et al. (2009) also studied the performance
of concrete paving blocks with crumb rubber, reporting a high toughness
resistance due to the energy-absorbing capacity. These means that tyre waste
concrete may be recommended for concrete structures located in areas of
severe earthquake risk and also for the production of railway sleepers.
Modulus of elasticity
Since concrete with rubber waste has low compressive strength and a
correlation exists between compressive strength and the modulus of elasticity,
they should also possess lower modulus of elasticity. however, Skripkiunas
et al. (2007) compared concretes with similar compressive strength (a
reference one and another with 3.3% of crumb rubber) obtaining different
static modulus of elasticity, 29.6 gPa versus 33.2 gPa for the reference
concrete just 11% higher. The explanation for this behaviour is related to
the low modulus of elasticity of rubber waste (anison, 1964). other authors
(Turatsinze, 2007) report a decrease in the modulus of elasticity of 40% when
the same percentage reduction takes place for compressive strength. Khaloo
et al. (2008) confirmed that the inclusion of tyre rubber particles leads to
a concrete with high ductility. Zheng et al. (2008a, 2008b) mentioned that
crumb rubber (80% <2.62 mm) has less of an influence on the modulus of
elasticity than crushed rubber (15-40 mm). Turatsinze and garros (2008)
