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TECHNICAL PAPER
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(a) (b)
Figure 4: Mass loss rate of steel reinforcement in FRCs and ECC prism specimens.
capacity and stiffness was observed in the R/FRC specimens. For
electrochemistry point of view, the presence of wide longitudinal
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As for the ECC cover, the presence of multiple fine microcracks
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load capacity of R/ECC specimen after 4-d accelerated corrosion
3.4 Residual flexural load capacity and failure was 61% that of the pristine R/ECC specimen, which is about
two and four times that of the residual flexural load capacity of
modes
R/FRC specimens subject to the same duration of accelerated
The load-deflection curves and failure modes of reinforced FRC corrosion. This again is attributed to the high ductility and
(R/FRC) and reinforced ECC (R/ECC) before and after the damage tolerance of ECC which slows down the corrosion and
accelerated corrosion are summarized in Figure 5 and Table 4, fundamentally alters the brittle failure mode introduced by steel
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pristine reinforced prism specimens before corrosion. As can be significant reduction of the cross-sectional area of the steel bar,
seen, R/ECC showed the highest flexural load capacity of 35.2kN, which also reduces the load-carrying capacity of corroded R/FRC
which is about 50% higher than that of R/FRCs. Figures 5(b) and specimens. While corrosion of steel bar in R/ECC is more
5(c) show the typical load-deflection curves of reinforced prism uniform which reduces local stress concentration in steel, and
specimens after 2-d and 4-d accelerated corrosion, respectively. thus the corroded R/ECC specimens can maintain a higher level
As can be seen, a significant reduction of the ultimate load of load-carrying capacity.
Table 4: Flexural strength, deflection and failure mode of reinforced prisms
Mix iD Corrosion uLtiMate % retaineD LoaD DefLeCtion faiLure
Duration (d) LoaD (kn) CapaCitY (mm) MoDe
FRC 1 0 23.6± 2.15 100 1.38 ±0.03 Shear
2 15.9 ±2.26 67 0.77 ±0.02 Bond
4 3.9 ±0.61 15 0.82 ±0.04 Bond
FRC 2 0 24.9 ±1.98 100 1.33 ±0.03 Shear
2 16.7 ±0.88 67 0.78 ±0.03 Shear
4 6.5 ±0.62 26 0.84 ±0.07 Bond
FRC 3 0 27.8 ±1.03 100 1.80 ±0.10 Shear
2 20.7 ±2.02 74 1.07 ±0.04 Shear
4 10.5 ±0.71 38 0.86 ±0.13 Shear
ECC 0 35.2 ±0.78 100 1.56 ±0.07 Bending
2 28.0 ±1.95 80 1.84 ±0.06 Bending
4 21.5 ±0.99 61 1.49 ±0.04 Bending
14 The IndIan ConCreTe Journal | deCember 2019
