Page 98 - New Trends in Eco efficient and Recycled Concrete

72 New Trends in Eco-efficient and Recycled Concrete

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1 50% 25%
70%
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2 50% 25%
70%
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3 50% 25%
70%
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4 40% 20%
80% 60%
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5 20% 15% 10% 5%
Reference 6 45% 30% 5%
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7 50% 0%
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8 20%
50%
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9 50% 25%
75%
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10 20%
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11 20%
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0 2 4 6
Splitting tensile strength (MPa)
Figure 3.10 Variation of splitting tensile strength of PA concrete with RPA%. 1, 2, 3 (Choi
et al., 2005): uniform shape PET; 4 (Tang et al., 2008): uniform shape EPS; 5 (Batayneh
et al., 2007): non-uniform shape aggregate; 6 (Kou et al., 2009): non-uniform shape PVC;
7(Lima et al., 2010): non-uniform shape EVA; 8 (Wang and Meyer, 2012): non-uniform
shape HIPS; 9 (Juki et al., 2013): non-uniform shape PET; 10, 11 (Ozbakkaloglu et al.,
2017): non-uniform shape PP. % values represent RPA%. PA, Plastic aggregate; PET,
polyethylene terephthalate; EPS, expanded polystyrene; EVA, ethylene-vinyl acetate;
PP, polypropylene; HIPS, high-impact polystyrene; PVC, polyvinyl chloride.

flexural strength, the splitting tensile strength of PA concrete is lower than that of
conventional concrete and it decreases with an increase in RPA%.
Fig. 3.11 shows the variation of 28-day splitting tensile strength of PF concrete
with RPF%. As can be seen in Fig. 3.11, the splitting tensile strength of PF con-
crete increases with an increase in RPF%. This observation can be because of the
bridging effect of fibres across the split portions of the concrete where the stresses
were transferred from the concrete matrix to the fibres (Song et al., 2005).
However, some researchers reported that the splitting tensile strength of concrete
only improves when RPF% increases up to a certain threshold beyond which no
further increases are observed (Wang et al., 1994; Kayali et al., 1999, 2003;
Ramadevi and Manju, 2012; Nibudey et al., 2013). Khadakbhavi et al. (2010)
found that the PF geometry influences the splitting tensile strength of concrete.
They reported that the splitting tensile strength of concrete containing 0.6%
HDPE fibres with aspect ratios of 20, 40, 60, 80 and 100 increased by 10%, 23%,
37%, 22% and 5%, respectively.